Most bad leadership decisions are not made by bad leaders. They are made by capable, experienced people working fast, under pressure, with a confident story in their heads. A depot manager signs off a new routing plan because the numbers "feel right". A board approves a warehouse automation project on a timeline nobody has checked against similar projects. A team agrees in twenty minutes because nobody wants to be the one who slows things down.
Psychologists have spent fifty years mapping exactly how this happens. The errors are not random. They are predictable, they get worse under stress and fatigue, and they hit experts as hard as beginners. The good news is that the same research shows which defences work. Some are as simple as a five-minute exercise before a meeting.
We reviewed more than 70 peer-reviewed studies, meta-analyses, books by leading researchers and official reports to identify the 25 decision traps that do the most damage to leaders under pressure. Each trap comes with the evidence, APA citations you can check, and three practical ways to beat it. Where a famous finding has struggled to replicate, we tell you.
The short version: Your judgment is not as reliable as it feels, especially when you are rushed, tired or surrounded by people who agree with you. You cannot think your way out of bias by trying harder. You beat it with better process: outside views, independent opinions, premortems, checklists and keeping score.
Key takeaways
- Experts are badly overconfident. When senior finance executives gave 80% confidence ranges for stock market returns, the real result fell inside the range only 36% of the time (Ben-David et al., 2013).
- Process beats analysis by a factor of six. In a study of 1,048 major business decisions, the quality of the decision process explained far more of the outcome than the depth of the analysis (Lovallo & Sibony, 2010).
- Nine out of ten big projects run over budget. Across 258 transport infrastructure projects, rail projects overran their cost estimates by 44.7% on average (Flyvbjerg et al., 2002).
- Teams ignore what only one person knows. A meta-analysis of 65 studies found groups with unevenly shared information were eight times less likely to find the best answer (Lu et al., 2012).
- Fatigue looks like alcohol. After 17 to 19 hours without sleep, performance on some tests was as bad as or worse than at a blood alcohol level of 0.05% (Williamson & Feyer, 2000).
- Debiasing can be trained. A single training session cut measured bias by at least 23% two months later (Morewedge et al., 2015).
How to read this guide: The 25 traps are grouped into four parts: your own mind under pressure, the traps that lock you into failing plans, the traps that groups fall into, and the process fixes most leaders skip. Citations in brackets lead to the full reference list at the bottom. Effects found in studies are averages from specific samples, and your situation may differ. This article is general information, not financial, legal, medical or safety-engineering advice.
Part 1: Your brain under pressure

Trap 1: Your confidence ranges are far too narrow
Overconfidence comes in three forms: thinking you are better than you are, thinking you are better than others, and being too sure your estimates are precise (Moore & Healy, 2008). The third, overprecision, is the most stubborn and the most dangerous for leaders who forecast. Ben-David et al. (2013) analysed more than 13,300 forecasts by chief financial officers over ten years. Their 80% confidence intervals for market returns contained the actual result only 36% of the time. Executives who were miscalibrated about the market were also miscalibrated about their own firms, and their companies invested more and borrowed more. The same pattern shows up at the very top. CEOs classified as overconfident made investment decisions that tracked their available cash more closely (Malmendier & Tate, 2005), and they were more likely to make acquisitions, especially diversifying ones, which the market greeted more negatively (Malmendier & Tate, 2008).
How to beat it:
- Never accept a single-number forecast. Ask for a low, likely and high estimate, then ask, "What would have to happen for us to land outside this range?"
- Widen your ranges deliberately. If your 80% range has never been wrong, it is too narrow.
- Record your estimates for volumes, lead times and costs, and check them against what actually happened each quarter.
Trap 2: You go looking for proof, not for truth
Confirmation bias is the habit of seeking, noticing and remembering evidence that supports what we already believe. Nickerson (1998) reviewed the evidence and called it one of the most widespread and powerful biases in human reasoning, appearing in many guises from science to courtrooms. Under pressure it gets worse, because checking a favoured idea feels like progress while searching for disconfirming evidence feels like delay. One of the most reliable fixes is surprisingly simple. Lord et al. (1984) found that asking people to "consider the opposite" reduced biased judgment more than asking them to be fair and unbiased.
How to beat it:
- Before you commit, write down what evidence would prove you wrong, then go and look for it.
- Ask your team to build the best case against the preferred option, not just to "poke holes".
- Replace "Does this support the plan?" with "If the plan were wrong, what would we expect to see?"
Trap 3: The first number in the room steers everyone
In a classic experiment, people spun a wheel of fortune rigged to land on 10 or 65, then estimated the percentage of African countries in the United Nations. Those who saw 10 gave a median estimate of 25; those who saw 65 gave 45 (Tversky & Kahneman, 1974). Expertise does not protect you. Experienced real estate agents' valuations of the same house moved with the listing price they were shown, though they denied it influenced them (Northcraft & Neale, 1987). Experienced judges' sentences were pulled toward demands they knew were random, even ones they set by rolling dice (Englich et al., 2006). Anchoring is also one of the effects that has replicated well in large multi-lab studies (Klein et al., 2014).
How to beat it:
- Ask where every key number came from, and who put the first figure on the table (Kahneman et al., 2011).
- Build a second estimate from a completely different starting point, such as a benchmark or bottom-up count, before you look at the proposed figure.
- In negotiations with carriers or suppliers, set your own reference point in writing before the first offer arrives.
Trap 4: Vivid stories beat boring statistics
We judge how likely something is by how easily examples come to mind. Tversky and Kahneman (1973) called this the availability heuristic. Ease of recall is shaped by drama, recency and media coverage, not by true frequency. Lichtenstein et al. (1978) found people overestimated the frequency of dramatic causes of death, such as accidents and homicide, and underestimated quieter killers like many diseases. For leaders, the last incident, the loudest customer or the most recent near miss can dominate a decision that should rest on the full record.
How to beat it:
- When a single vivid case is driving a decision, ask for the base rate: how often does this actually happen across all our sites or shipments?
- Keep simple trend data for incidents, delays and complaints so you can compare the latest story with the long-run pattern.
- Ask, "Is this the most important problem, or just the most memorable one?"
Trap 5: The same facts, framed differently, flip your choice
Prospect theory showed that people weigh losses more heavily than equivalent gains and judge outcomes relative to a reference point (Kahneman & Tversky, 1979). Framing exploits this. When a disease programme was described in terms of lives saved, 72% of participants chose the safe option. When the identical programme was described in terms of lives lost, 78% chose the risky option instead (Tversky & Kahneman, 1981). Gain-versus-loss framing effects have also held up in large replication projects (Klein et al., 2014). A cost-cutting plan framed as "protecting 80% of jobs" and one framed as "cutting 20% of jobs" will not get the same reaction, from you or your board.
How to beat it:
- Restate every major option in both frames, as gains and as losses, before deciding.
- Check whether your reference point is fair. Are you comparing against last year, the budget, a competitor or a wish?
- When presenting to others, show the full picture in both frames so you inform rather than steer.
Trap 6: Stress makes you grab the first workable answer
Acute stress weakens the prefrontal cortex, the brain region that handles flexible, deliberate thinking, and shifts control toward faster, habitual responses (Arnsten, 2009). In an experiment by Keinan (1987), people under threat of stress were significantly more likely to offer a solution before considering all the alternatives and to scan options in a disorganised way, and this predicted wrong answers. A meta-analysis of 32 datasets with 1,829 participants found stress led to more disadvantageous, reward-seeking and risky decisions overall. The effect was small (d = .17) but larger in situations where risk-taking was a bad idea (Starcke & Brand, 2016).
How to beat it:
- Under pressure, force a minimum of two real alternatives onto the table before choosing.
- Prepare decision rules and escalation thresholds in calm times, so a crisis triggers a plan instead of improvisation.
- If the decision can wait ten minutes, take them. A short pause to list options is cheap; a stressed snap judgment is not.
Trap 7: Deciding when you are exhausted
Fatigue is a real decision risk, and leaders in logistics and operations face it constantly. Williamson and Feyer (2000) tested 39 people, 30 of them from the transport industry. After 17 to 19 hours awake, performance on some tests was equivalent to or worse than at 0.05% blood alcohol, with response speeds up to 50% slower. Harrison and Horne (2000) found sleep loss particularly harms decisions that involve the unexpected, revising plans and communicating clearly, exactly what a crisis demands. Be careful with the popular idea of "decision fatigue", though. A famous study suggested parole approvals fell from about 65% to nearly zero before judges' breaks (Danziger et al., 2011), but critics showed case ordering and timing could explain much of the pattern (Weinshall-Margel & Shapard, 2011; Glöckner, 2016). Large preregistered replications of "ego depletion", the theory behind decision fatigue, found effects close to zero (Hagger et al., 2016; Vohs et al., 2021).
How to beat it:
- Schedule irreversible, high-stakes decisions for when you are rested, not at the end of a double shift.
- In long incidents, hand over formally to a fresh decision-maker rather than pushing through the night.
- Treat sleep loss as a measurable risk. The evidence is much stronger for sleep than for willpower "running out".
Trap 8: You see bias in everyone except yourself
Pronin et al. (2002) found people consistently rated themselves as less susceptible to common biases than the average person. They could spot bias in others but not in their own thinking. Scopelliti et al. (2015) developed a measure of this "bias blind spot" and found people high on it were more likely to ignore advice from others. This is why reading about biases, on its own, rarely helps. Kahneman et al. (2011) make the point directly: because you cannot see your own biases, review should be done by people independent of the team making the recommendation.
How to beat it:
- Assume you are biased on every important call, and build in someone whose job is to check your reasoning.
- Seek out advice before you have announced a view, when it is still cheap to change your mind.
- Ask a trusted colleague, "Where do you think I'm most likely to be fooling myself on this?"
Part 2: Commitment traps: plans, projects and sunk costs

Trap 9: Your plan assumes everything goes right
The planning fallacy is our tendency to underestimate how long tasks will take, even when we know similar tasks have run late before. Buehler et al. (1994) asked students to predict when they would finish their theses. On average they predicted about 34 days; the real average was about 55 days, and only around 30% finished by their own estimate. Even their "worst case" predictions were too optimistic. People focus on their specific plan and the steps ahead, and neglect their own track record. Lovallo and Kahneman (2003) argue that executives fall into the same trap, overweighting their plans and underweighting the history of similar projects.
How to beat it:
- Before accepting a timeline, ask how long the last three similar projects actually took.
- Plan for the pessimistic case, not just the likely one, and set buffers explicitly rather than hiding them.
- Break big launches, such as a new site or system, into stages with honest checkpoints.
Trap 10: You look at your project instead of the reference class
Kahneman and Lovallo (1993) distinguished the "inside view", which focuses on the details of the case at hand, from the "outside view", which asks how similar cases usually turn out. The inside view feels more informed but is consistently more optimistic. It is a business version of base-rate neglect: people judging by how well a case fits a story rather than by how often such cases succeed (Kahneman & Tversky, 1973; Kahneman, 2011). The cost of ignoring the outside view is huge. Flyvbjerg et al. (2002) studied 258 transport projects in 20 nations: nine out of ten went over budget, and rail projects averaged a 44.7% overrun. In a later book drawing on a database of more than 16,000 projects, Flyvbjerg and Gardner (2023) report that only about one in two hundred came in on budget, on time and delivering the promised benefits. The fix, reference-class forecasting, starts from the outcomes of comparable past projects and adjusts from there (Flyvbjerg, 2008).
How to beat it:
- For any major investment, find a reference class of at least five to ten comparable projects and note their real cost and schedule overruns.
- Start your estimate from that distribution, then adjust for genuine differences, not the other way round.
- Ask suppliers and integrators for the typical overrun on projects like yours, not just their quote.
Trap 11: You keep paying because you already paid
Rationally, money and effort already spent should not affect what you do next. Only future costs and benefits matter. In practice, sunk costs pull us forward. Arkes and Blumer (1985) showed this in a series of experiments, and in a field study where theatre customers who paid full price for season tickets went to more plays early in the season than those who got a discount. In business, sunk costs keep failing systems, unprofitable routes and doomed contracts alive. A meta-analysis of 35 years of research confirms that sunk costs are one of the strongest drivers of continuing a failing course of action (Sleesman et al., 2012).
How to beat it:
- Ask the clean-slate question: "If we were starting today, with what we know now, would we invest in this?"
- Present future costs and benefits separately from money already spent, so the past can't hide in the totals.
- Make it normal to stop projects. Celebrate a well-timed exit as good management, not as failure.
Trap 12: You double down to prove you were right
Escalation of commitment goes beyond sunk costs. It is personal. Staw (1976) found business students who were personally responsible for an initial investment that failed put more money into it than those who inherited the decision. Sleesman et al. (2012) confirmed personal responsibility as a key driver across decades of studies. The real world shows the same pattern. Staw et al. (1997) tracked 132 California banks over nine years. When senior executives left, banks increased provisions for bad loans and wrote off more of them, suggesting the original decision-makers had been holding on to problem loans.
How to beat it:
- Have someone who did not make the original call review whether to continue a struggling project.
- Agree "kill criteria" up front, such as cost, schedule or performance limits that trigger a formal review.
- Judge managers on the quality of their decisions and their willingness to change course, not on never having been wrong. In experiments, making people accountable for their decision process rather than the outcome reduced escalation (Simonson & Staw, 1992).
Trap 13: Doing nothing feels safer than it is
Samuelson and Zeckhauser (1988) showed in experiments and field data that people stick disproportionately with the current option, the status quo, even when alternatives are better. Defaults are so powerful they shape life-and-death choices. Johnson and Goldstein (2003) compared European countries and found that organ donation consent was dramatically higher where people were donors by default and had to opt out than where they had to opt in. For leaders, the status quo bias means "keep things as they are" rarely gets the same scrutiny as change, even though standing still has costs too.
How to beat it:
- Treat "no change" as an option with its own costs and risks, and put them on the page.
- Periodically review long-standing contracts, suppliers and processes as if choosing them for the first time.
- Use defaults deliberately and ethically. If a safety check or good practice matters, make it the default.
Trap 14: You only consider one option
Many organisational decisions are framed as "yes or no" on a single proposal. Nutt (1999) studied 356 decisions in medium and large organisations and found about half failed. Failure was linked to managers who imposed solutions, limited the search for alternatives and used power to push plans through, and these failure-prone tactics appeared in two of every three decisions. Heath and Heath (2013), drawing on another of Nutt's studies, report that only 29% of organisational decisions considered more than one alternative. Kahneman et al. (2011) include "Have credible alternatives been considered?" as a core question in their decision checklist.
How to beat it:
- Never decide on a single option. Ask for at least two genuinely different alternatives, including one that is cheaper or simpler.
- Try the "vanishing option" test: if this option were suddenly impossible, what would we do instead?
- Be wary when a proposal comes with one realistic choice and some obvious straw men.
Trap 15: You judge decisions by how they turned out
Good decisions can have bad outcomes, and bad decisions can get lucky. Yet people judge the quality of a decision largely by its result. Baron and Hershey (1988) found people rated the same decision as better, and the decision-maker as more competent, when the outcome happened to be good, even though they agreed outcomes should not matter. Hindsight makes it worse. Fischhoff (1975) showed that once people know what happened, they believe they would have predicted it, which hides how uncertain things really were. Leaders who reward lucky outcomes and punish unlucky ones teach their teams to gamble and to hide risk.
How to beat it:
- Write down your reasoning, key assumptions and confidence at the time of the decision, so you can review the thinking later, not just the result.
- In reviews, separate "Was the decision sound given what we knew?" from "Did it work out?"
- Recognise good process even when results disappoint, and question lucky wins before copying them.
Part 3: Group traps: when smart teams decide badly
Trap 16: Harmony becomes more important than accuracy
Irving Janis (1982) coined "groupthink" after studying policy fiascos such as the Bay of Pigs invasion. He described close-knit groups that suppressed doubts, felt invulnerable and rushed to agreement. The idea is powerful, but be precise about the evidence. Esser (1998) reviewed 25 years of research and found only partial, mixed support for Janis's full model. The most robust lesson is narrower: when leaders state their preference early and teams value cohesion over challenge, groups consider fewer options and less information. That is the pattern to guard against.
How to beat it:
- As the leader, speak last. Ask for views before revealing yours.
- Explicitly invite disagreement: "What are we not saying about this plan?"
- For big decisions, bring in an outside reviewer or a second team to test the conclusion independently.
Trap 17: Your team discusses what everyone already knows
Teams are supposed to pool knowledge. Often they don't. Stasser and Titus (1985) found that groups mostly discussed information all members already shared, while information held by only one member went unmentioned, so groups missed the best option. A meta-analysis of 65 studies and 3,189 groups confirmed it: groups mentioned far more shared than unique information, and groups facing these "hidden profiles" were eight times less likely to find the right solution than groups with full information (Lu et al., 2012). The key fact may be sitting with the night-shift supervisor, the new hire or the customer service lead, and never reach the room.
How to beat it:
- Before the meeting, ask each person to submit in writing what they know that others might not.
- Assign roles so each person is responsible for a specific area of knowledge, such as safety, customers or finance.
- Ask directly: "What does anyone here know that hasn't been said yet?"
Trap 18: Group discussion pushes everyone to extremes
Group polarisation is the tendency of a group to end up more extreme than its members' average starting view. Myers and Lamm (1976) reviewed the research and found the effect across many settings: like-minded groups shift further in the direction they were already leaning. Sunstein and Hastie (2015) describe how group discussion can amplify errors and create cascades, where people follow early speakers instead of revealing what they think. A cautious team can become paralysed; a bullish team can talk itself into a reckless bet.
How to beat it:
- Collect individual views or estimates privately before discussion starts.
- Build teams with genuinely different backgrounds and perspectives, not only different job titles.
- Compare the final group decision with the private starting views. If it has moved a long way, ask why.
Trap 19: The appointed devil's advocate is just theatre
Appointing a devil's advocate is a popular fix, and structured debate does help. In a study of middle managers, groups using devil's advocacy or dialectical inquiry made significantly higher-quality decisions than groups seeking consensus, though members accepted the decisions less readily (Schweiger et al., 1989). But role-played dissent is a weak substitute for the real thing. Nemeth et al. (2001) found that an authentic minority, someone who genuinely disagreed, produced more and better solutions than any form of devil's advocate. People can tell when dissent is a ritual, and they dismiss it.
How to beat it:
- Seek out people who really disagree, and protect them when they speak.
- If you use a devil's advocate, rotate the role and give them time and data to build a serious case.
- Reward people for raising concerns that improved a decision, even if the concern was eventually rejected.
Trap 20: Your experts disagree far more than you think
Bias is systematic error. Noise is random variability in judgments that should be identical. Kahneman et al. (2016) proposed the "noise audit": give professionals in the same unit the same cases and measure how much their judgments differ. Kahneman et al. (2021) describe an audit at an insurance company where executives expected underwriters' premiums for the same case to differ by about 10%. The median difference was 55%. Different supervisors grading the same incident, different planners quoting the same job, different managers rating the same performance: noise is everywhere, and it is usually invisible because people rarely judge the same case side by side.
How to beat it:
- Run a simple noise audit: give several people the same real case, such as a quote, incident or rating, and compare their answers.
- Use structured criteria and rating scales, and break big judgments into separate scored parts.
- Average several independent judgments. A "select crowd" of the five best-performing judges tends to be both accurate and robust (Mannes et al., 2014).
Part 4: Process traps: the fixes leaders skip
Trap 21: You trust brilliant analysis inside a weak process
Most organisations invest in better data and models. Fewer invest in how decisions are actually made. Lovallo and Sibony (2010) studied 1,048 major decisions, including investments, acquisitions and large capital spending. After controlling for industry, geography and company size, the quality of the decision process mattered more than the quantity and detail of the analysis by a factor of six. Kahneman et al. (2011) report that when organisations worked to reduce bias in their processes, returns were up to seven percentage points higher. The problem is widespread: in a 2018 survey of 1,259 managers, only 20% said their organisations excelled at decision making (McKinsey & Company, 2019). Note that both McKinsey studies rely on managers' own reports rather than controlled experiments.
How to beat it:
- For major decisions, invest as much attention in the process (who is involved, what alternatives were tested, how disagreement was handled) as in the spreadsheet.
- Make it legitimate to challenge assumptions in the meeting, not just in private.
- Separate the people who build the recommendation from the people who review it.
Trap 22: You skip the premortem
A postmortem tells you why the patient died. A premortem imagines the project has already failed and asks why. Gary Klein (2007) describes the method: before committing, the team imagines that it is months later and the plan has been a disaster, and each person writes down the reasons. Klein cites research by Mitchell et al. (1989) as showing that imagining an event has already happened, called prospective hindsight, increases the ability to identify reasons for future outcomes by 30%. The technique also makes it safe for quiet sceptics to speak up, because finding failure points becomes the task, not disloyalty.
How to beat it:
- Before signing off any major plan, run a 20-minute premortem: "It is a year from now and this failed. Write down why."
- Collect the reasons from everyone, starting with the most junior people, and add the top risks to the plan.
- Repeat a short premortem at key project milestones, especially before peak season or a go-live.
Trap 23: You trust your gut where it hasn't earned it
Kahneman and Klein (2009), long on opposite sides of the intuition debate, agreed on when gut feel can be trusted. Intuition is reliable only in environments that are regular enough to be predictable, and where the person has had long practice with fast, clear feedback. A firefighter or an experienced forklift trainer may qualify; a manager forecasting next year's freight market probably doesn't. Where those conditions are missing, simple formulas often win. A meta-analysis of clinical versus mechanical prediction found formulas were on average about 10% more accurate than human experts, and substantially better in a third to nearly half of studies (Grove et al., 2000; see also Dawes et al., 1989).
How to beat it:
- Ask two questions about any gut call: is this environment predictable, and have I had real, fast feedback on decisions like this?
- Where intuition hasn't been earned, use a simple scoring rule or checklist, and let intuition adjust it only at the end.
- In hiring and supplier selection, score structured criteria before any open discussion.
Trap 24: Nobody keeps score of your forecasts
Philip Tetlock (2005) tracked forecasts by 284 experts on political and economic trends over many years. On average, they performed barely better than chance and worse than simple statistical rules, and the most famous and confident were often the least accurate. But forecasting can be improved. In a multi-year forecasting tournament sponsored by the U.S. intelligence community, Tetlock's Good Judgment Project found that training in probabilistic reasoning, working in teams and tracking the best performers all improved accuracy (Mellers et al., 2014). The top forecasters, "superforecasters", stayed accurate year after year (Mellers et al., 2015). By the project's own account, its forecasts beat the official control group by 60% in year one and 78% in year two (Tetlock & Gardner, 2015).
How to beat it:
- Turn vague forecasts ("demand should pick up") into specific, dated probabilities ("70% chance volume is up 5% by March").
- Keep a forecast log for your team and review accuracy every quarter, without blame.
- Average several independent estimates, including two of your own made at different times. Even a single person's averaged guesses can beat their first answer (Vul & Pashler, 2008; Herzog & Hertwig, 2009).
Trap 25: You rely on willpower instead of a checklist
The most reliable way to beat bias is not to try harder; it is to change the routine. Kahneman et al. (2011) offer a 12-question checklist for reviewing big recommendations, covering self-interest, overconfidence, anchoring, sunk costs and whether credible alternatives were considered. Checklists work in high-stakes fields. When eight hospitals around the world introduced a 19-item surgical safety checklist, inpatient deaths fell from 1.5% to 0.8% and complications from 11.0% to 7.0% (Haynes et al., 2009). Training helps too. One-off debiasing games reduced bias by at least 23% two months later (Morewedge et al., 2015), and trained graduate students were 19% less likely to choose an inferior, confirmation-driven solution in a realistic business case (Sellier et al., 2019).
How to beat it:
- Adopt a short decision checklist for major calls: alternatives, base rates, where the numbers came from, dissent, worst case and kill criteria.
- Keep a one-page decision record for every big call: options, reasoning, confidence and what would change your mind.
- Train your team in common biases with practice and feedback, not just a slide deck.
A note on the evidence: Psychology has been through a replication crisis. When 100 published studies were repeated, only about a third to a half produced the same results (Open Science Collaboration, 2015). Core findings in this guide, such as anchoring and framing, have held up well in large replications (Klein et al., 2014), while others, such as ego depletion, have not (Hagger et al., 2016; Vohs et al., 2021). We have flagged the weaker areas where they appear.
Your 10-point decision action plan
You will never remove bias from your own head. You can stop it from running your decisions. Across all 25 traps, the same defences keep coming up:
- Slow down the irreversible calls. Decide fast on reversible choices; give one-way doors a proper process.
- Always have two real options. Never approve a single proposal without a genuine alternative.
- Take the outside view first. Start with how similar projects really turned out, then adjust.
- Get independent views before discussion. Written estimates and opinions first, debate second, leader last.
- Run a premortem. Imagine failure, list the reasons, fix the biggest ones.
- Set kill criteria up front. Agree in advance what results would make you stop or rethink.
- Protect real dissent. Seek out the people who genuinely disagree and make it safe for them.
- Keep score. Log forecasts and decision reasoning, then review them honestly.
- Respect fatigue. Don't make big calls exhausted; hand over when you need to.
- Use a checklist. A short, standard set of questions beats good intentions every time.
Want to make better calls when the pressure is on? Take our free Leadership Flex Check to see how you lead under pressure, then explore BLTI's leadership, decision-making and operations courses.
Frequently asked questions
What are the most common cognitive biases in leadership decision making?
The most damaging for leaders include overconfidence, confirmation bias, anchoring, the planning fallacy, sunk-cost thinking, escalation of commitment and group effects such as groupthink and hidden profiles. Kahneman et al. (2011) built their decision checklist around many of these.
Can you actually reduce cognitive bias?
Yes, but mostly through process rather than willpower. Techniques such as considering the opposite, reference-class forecasting, premortems and checklists have evidence behind them, and short debiasing training has produced lasting reductions in bias (Lord et al., 1984; Morewedge et al., 2015; Sellier et al., 2019).
What is a premortem and how do you run one?
A premortem asks a team to imagine that a plan has already failed and to write down why (Klein, 2007). Allow about 20 minutes, collect everyone's reasons, start with the most junior voices, and turn the top risks into changes to the plan.
Is decision fatigue real?
The evidence is weaker than its popularity suggests. The famous parole-judge study has been seriously challenged (Glöckner, 2016), and large replications of ego depletion found effects near zero (Hagger et al., 2016; Vohs et al., 2021). Sleep deprivation, however, clearly impairs performance and decisions (Williamson & Feyer, 2000; Harrison & Horne, 2000).
What is reference-class forecasting?
It means estimating a project's cost or timeline by starting from the actual results of a group of similar past projects, rather than building up from your own plan. It was developed to counter optimism bias in large projects (Flyvbjerg, 2008; Kahneman & Lovallo, 1993).
What is the difference between bias and noise?
Bias is error that pushes judgments consistently in one direction. Noise is unwanted variability: different people, or the same person at different times, reaching different judgments on the same case (Kahneman et al., 2021). Both cost money, and they need different fixes.
About this research
This guide was compiled by the Better Leaders Training Institute (BLTI) research team. Every source below was checked for authors, year, title, publisher and DOI or stable link, using publisher records and the Crossref database. We prioritised peer-reviewed studies, meta-analyses, preregistered replications and books by leading researchers. Where a figure comes from a consulting firm's survey, a project's own account or a secondary summary, we say so in the text, and we flag findings that have struggled to replicate. Findings from individual studies describe averages and specific samples; your organisation may differ. This article is general information, not financial, legal, medical or safety-engineering advice.
References
Arkes, H. R., & Blumer, C. (1985). The psychology of sunk cost. Organizational Behavior and Human Decision Processes, 35(1), 124–140. https://doi.org/10.1016/0749-5978(85)90049-4
Arnsten, A. F. T. (2009). Stress signalling pathways that impair prefrontal cortex structure and function. Nature Reviews Neuroscience, 10(6), 410–422. https://doi.org/10.1038/nrn2648
Baron, J., & Hershey, J. C. (1988). Outcome bias in decision evaluation. Journal of Personality and Social Psychology, 54(4), 569–579. https://doi.org/10.1037/0022-3514.54.4.569
Ben-David, I., Graham, J. R., & Harvey, C. R. (2013). Managerial miscalibration. The Quarterly Journal of Economics, 128(4), 1547–1584. https://doi.org/10.1093/qje/qjt023
Buehler, R., Griffin, D., & Ross, M. (1994). Exploring the "planning fallacy": Why people underestimate their task completion times. Journal of Personality and Social Psychology, 67(3), 366–381. https://doi.org/10.1037/0022-3514.67.3.366
Danziger, S., Levav, J., & Avnaim-Pesso, L. (2011). Extraneous factors in judicial decisions. Proceedings of the National Academy of Sciences, 108(17), 6889–6892. https://doi.org/10.1073/pnas.1018033108
Dawes, R. M., Faust, D., & Meehl, P. E. (1989). Clinical versus actuarial judgment. Science, 243(4899), 1668–1674. https://doi.org/10.1126/science.2648573
Englich, B., Mussweiler, T., & Strack, F. (2006). Playing dice with criminal sentences: The influence of irrelevant anchors on experts' judicial decision making. Personality and Social Psychology Bulletin, 32(2), 188–200. https://doi.org/10.1177/0146167205282152
Esser, J. K. (1998). Alive and well after 25 years: A review of groupthink research. Organizational Behavior and Human Decision Processes, 73(2–3), 116–141. https://doi.org/10.1006/obhd.1998.2758
Fischhoff, B. (1975). Hindsight is not equal to foresight: The effect of outcome knowledge on judgment under uncertainty. Journal of Experimental Psychology: Human Perception and Performance, 1(3), 288–299. https://doi.org/10.1037/0096-1523.1.3.288
Flyvbjerg, B. (2008). Curbing optimism bias and strategic misrepresentation in planning: Reference class forecasting in practice. European Planning Studies, 16(1), 3–21. https://doi.org/10.1080/09654310701747936
Flyvbjerg, B., & Gardner, D. (2023). How big things get done: The surprising factors that determine the fate of every project, from home renovations to space exploration and everything in between. Currency.
Flyvbjerg, B., Holm, M. S., & Buhl, S. (2002). Underestimating costs in public works projects: Error or lie? Journal of the American Planning Association, 68(3), 279–295. https://doi.org/10.1080/01944360208976273
Glöckner, A. (2016). The irrational hungry judge effect revisited: Simulations reveal that the magnitude of the effect is overestimated. Judgment and Decision Making, 11(6), 601–610. https://doi.org/10.1017/S1930297500004812
Grove, W. M., Zald, D. H., Lebow, B. S., Snitz, B. E., & Nelson, C. (2000). Clinical versus mechanical prediction: A meta-analysis. Psychological Assessment, 12(1), 19–30. https://doi.org/10.1037/1040-3590.12.1.19
Hagger, M. S., Chatzisarantis, N. L. D., Alberts, H., Anggono, C. O., Batailler, C., Birt, A. R., Brand, R., Brandt, M. J., Brewer, G., Bruyneel, S., Calvillo, D. P., Campbell, W. K., Cannon, P. R., Carlucci, M., Carruth, N. P., Cheung, T., Crowell, A., De Ridder, D. T. D., Dewitte, S., … Zwienenberg, M. (2016). A multilab preregistered replication of the ego-depletion effect. Perspectives on Psychological Science, 11(4), 546–573. https://doi.org/10.1177/1745691616652873
Harrison, Y., & Horne, J. A. (2000). The impact of sleep deprivation on decision making: A review. Journal of Experimental Psychology: Applied, 6(3), 236–249. https://doi.org/10.1037/1076-898X.6.3.236
Haynes, A. B., Weiser, T. G., Berry, W. R., Lipsitz, S. R., Breizat, A.-H. S., Dellinger, E. P., Herbosa, T., Joseph, S., Kibatala, P. L., Lapitan, M. C. M., Merry, A. F., Moorthy, K., Reznick, R. K., Taylor, B., & Gawande, A. A. (2009). A surgical safety checklist to reduce morbidity and mortality in a global population. New England Journal of Medicine, 360(5), 491–499. https://doi.org/10.1056/NEJMsa0810119
Heath, C., & Heath, D. (2013). Decisive: How to make better choices in life and work. Crown Business.
Herzog, S. M., & Hertwig, R. (2009). The wisdom of many in one mind: Improving individual judgments with dialectical bootstrapping. Psychological Science, 20(2), 231–237. https://doi.org/10.1111/j.1467-9280.2009.02271.x
Janis, I. L. (1982). Groupthink: Psychological studies of policy decisions and fiascoes (2nd ed.). Houghton Mifflin.
Johnson, E. J., & Goldstein, D. (2003). Do defaults save lives? Science, 302(5649), 1338–1339. https://doi.org/10.1126/science.1091721
Kahneman, D. (2011). Thinking, fast and slow. Farrar, Straus and Giroux.
Kahneman, D., & Klein, G. (2009). Conditions for intuitive expertise: A failure to disagree. American Psychologist, 64(6), 515–526. https://doi.org/10.1037/a0016755
Kahneman, D., & Lovallo, D. (1993). Timid choices and bold forecasts: A cognitive perspective on risk taking. Management Science, 39(1), 17–31. https://doi.org/10.1287/mnsc.39.1.17
Kahneman, D., Lovallo, D., & Sibony, O. (2011). Before you make that big decision. Harvard Business Review, 89(6), 50–60. https://hbr.org/2011/06/the-big-idea-before-you-make-that-big-decision
Kahneman, D., Rosenfield, A. M., Gandhi, L., & Blaser, T. (2016). Noise: How to overcome the high, hidden cost of inconsistent decision making. Harvard Business Review, 94(10), 38–46. https://hbr.org/2016/10/noise
Kahneman, D., Sibony, O., & Sunstein, C. R. (2021). Noise: A flaw in human judgment. Little, Brown Spark.
Kahneman, D., & Tversky, A. (1973). On the psychology of prediction. Psychological Review, 80(4), 237–251. https://doi.org/10.1037/h0034747
Kahneman, D., & Tversky, A. (1979). Prospect theory: An analysis of decision under risk. Econometrica, 47(2), 263–291. https://doi.org/10.2307/1914185
Keinan, G. (1987). Decision making under stress: Scanning of alternatives under controllable and uncontrollable threats. Journal of Personality and Social Psychology, 52(3), 639–644. https://doi.org/10.1037/0022-3514.52.3.639
Klein, G. (2007). Performing a project premortem. Harvard Business Review, 85(9), 18–19. https://hbr.org/2007/09/performing-a-project-premortem
Klein, R. A., Ratliff, K. A., Vianello, M., Adams, R. B., Jr., Bahník, Š., Bernstein, M. J., Bocian, K., Brandt, M. J., Brooks, B., Brumbaugh, C. C., Cemalcilar, Z., Chandler, J., Cheong, W., Davis, W. E., Devos, T., Eisner, M., Frankowska, N., Furrow, D., Galliani, E. M., … Nosek, B. A. (2014). Investigating variation in replicability: A "many labs" replication project. Social Psychology, 45(3), 142–152. https://doi.org/10.1027/1864-9335/a000178
Lichtenstein, S., Slovic, P., Fischhoff, B., Layman, M., & Combs, B. (1978). Judged frequency of lethal events. Journal of Experimental Psychology: Human Learning and Memory, 4(6), 551–578. https://doi.org/10.1037/0278-7393.4.6.551
Lord, C. G., Lepper, M. R., & Preston, E. (1984). Considering the opposite: A corrective strategy for social judgment. Journal of Personality and Social Psychology, 47(6), 1231–1243. https://doi.org/10.1037/0022-3514.47.6.1231
Lovallo, D., & Kahneman, D. (2003). Delusions of success: How optimism undermines executives' decisions. Harvard Business Review, 81(7), 56–63. https://hbr.org/2003/07/delusions-of-success-how-optimism-undermines-executives-decisions
Lovallo, D., & Sibony, O. (2010, March 1). The case for behavioral strategy. McKinsey Quarterly. https://www.mckinsey.com/capabilities/strategy-and-corporate-finance/our-insights/the-case-for-behavioral-strategy
Lu, L., Yuan, Y. C., & McLeod, P. L. (2012). Twenty-five years of hidden profiles in group decision making: A meta-analysis. Personality and Social Psychology Review, 16(1), 54–75. https://doi.org/10.1177/1088868311417243
Malmendier, U., & Tate, G. (2005). CEO overconfidence and corporate investment. The Journal of Finance, 60(6), 2661–2700. https://doi.org/10.1111/j.1540-6261.2005.00813.x
Malmendier, U., & Tate, G. (2008). Who makes acquisitions? CEO overconfidence and the market's reaction. Journal of Financial Economics, 89(1), 20–43. https://doi.org/10.1016/j.jfineco.2007.07.002
Mannes, A. E., Soll, J. B., & Larrick, R. P. (2014). The wisdom of select crowds. Journal of Personality and Social Psychology, 107(2), 276–299. https://doi.org/10.1037/a0036677
McKinsey & Company. (2019, April). Decision making in the age of urgency [Survey report]. https://www.mckinsey.com/capabilities/people-and-organizational-performance/our-insights/decision-making-in-the-age-of-urgency
Mellers, B., Stone, E., Murray, T., Minster, A., Rohrbaugh, N., Bishop, M., Chen, E., Baker, J., Hou, Y., Horowitz, M., Ungar, L., & Tetlock, P. (2015). Identifying and cultivating superforecasters as a method of improving probabilistic predictions. Perspectives on Psychological Science, 10(3), 267–281. https://doi.org/10.1177/1745691615577794
Mellers, B., Ungar, L., Baron, J., Ramos, J., Gurcay, B., Fincher, K., Scott, S. E., Moore, D., Atanasov, P., Swift, S. A., Murray, T., Stone, E., & Tetlock, P. E. (2014). Psychological strategies for winning a geopolitical forecasting tournament. Psychological Science, 25(5), 1106–1115. https://doi.org/10.1177/0956797614524255
Mitchell, D. J., Russo, J. E., & Pennington, N. (1989). Back to the future: Temporal perspective in the explanation of events. Journal of Behavioral Decision Making, 2(1), 25–38. https://doi.org/10.1002/bdm.3960020103
Moore, D. A., & Healy, P. J. (2008). The trouble with overconfidence. Psychological Review, 115(2), 502–517. https://doi.org/10.1037/0033-295X.115.2.502
Morewedge, C. K., Yoon, H., Scopelliti, I., Symborski, C. W., Korris, J. H., & Kassam, K. S. (2015). Debiasing decisions: Improved decision making with a single training intervention. Policy Insights from the Behavioral and Brain Sciences, 2(1), 129–140. https://doi.org/10.1177/2372732215600886
Myers, D. G., & Lamm, H. (1976). The group polarization phenomenon. Psychological Bulletin, 83(4), 602–627. https://doi.org/10.1037/0033-2909.83.4.602
Nemeth, C., Brown, K., & Rogers, J. (2001). Devil's advocate versus authentic dissent: Stimulating quantity and quality. European Journal of Social Psychology, 31(6), 707–720. https://doi.org/10.1002/ejsp.58
Nickerson, R. S. (1998). Confirmation bias: A ubiquitous phenomenon in many guises. Review of General Psychology, 2(2), 175–220. https://doi.org/10.1037/1089-2680.2.2.175
Northcraft, G. B., & Neale, M. A. (1987). Experts, amateurs, and real estate: An anchoring-and-adjustment perspective on property pricing decisions. Organizational Behavior and Human Decision Processes, 39(1), 84–97. https://doi.org/10.1016/0749-5978(87)90046-X
Nutt, P. C. (1999). Surprising but true: Half the decisions in organizations fail. Academy of Management Executive, 13(4), 75–90. https://doi.org/10.5465/ame.1999.2570556
Open Science Collaboration. (2015). Estimating the reproducibility of psychological science. Science, 349(6251), Article aac4716. https://doi.org/10.1126/science.aac4716
Pronin, E., Lin, D. Y., & Ross, L. (2002). The bias blind spot: Perceptions of bias in self versus others. Personality and Social Psychology Bulletin, 28(3), 369–381. https://doi.org/10.1177/0146167202286008
Samuelson, W., & Zeckhauser, R. (1988). Status quo bias in decision making. Journal of Risk and Uncertainty, 1(1), 7–59. https://doi.org/10.1007/BF00055564
Schweiger, D. M., Sandberg, W. R., & Rechner, P. L. (1989). Experiential effects of dialectical inquiry, devil's advocacy, and consensus approaches to strategic decision making. Academy of Management Journal, 32(4), 745–772. https://doi.org/10.5465/256567
Scopelliti, I., Morewedge, C. K., McCormick, E., Min, H. L., Lebrecht, S., & Kassam, K. S. (2015). Bias blind spot: Structure, measurement, and consequences. Management Science, 61(10), 2468–2486. https://doi.org/10.1287/mnsc.2014.2096
Sellier, A.-L., Scopelliti, I., & Morewedge, C. K. (2019). Debiasing training improves decision making in the field. Psychological Science, 30(9), 1371–1379. https://doi.org/10.1177/0956797619861429
Simonson, I., & Staw, B. M. (1992). Deescalation strategies: A comparison of techniques for reducing commitment to losing courses of action. Journal of Applied Psychology, 77(4), 419–426. https://doi.org/10.1037/0021-9010.77.4.419
Sleesman, D. J., Conlon, D. E., McNamara, G., & Miles, J. E. (2012). Cleaning up the big muddy: A meta-analytic review of the determinants of escalation of commitment. Academy of Management Journal, 55(3), 541–562. https://doi.org/10.5465/amj.2010.0696
Starcke, K., & Brand, M. (2016). Effects of stress on decisions under uncertainty: A meta-analysis. Psychological Bulletin, 142(9), 909–933. https://doi.org/10.1037/bul0000060
Stasser, G., & Titus, W. (1985). Pooling of unshared information in group decision making: Biased information sampling during discussion. Journal of Personality and Social Psychology, 48(6), 1467–1478. https://doi.org/10.1037/0022-3514.48.6.1467
Staw, B. M. (1976). Knee-deep in the big muddy: A study of escalating commitment to a chosen course of action. Organizational Behavior and Human Performance, 16(1), 27–44. https://doi.org/10.1016/0030-5073(76)90005-2
Staw, B. M., Barsade, S. G., & Koput, K. W. (1997). Escalation at the credit window: A longitudinal study of bank executives' recognition and write-off of problem loans. Journal of Applied Psychology, 82(1), 130–142. https://doi.org/10.1037/0021-9010.82.1.130
Sunstein, C. R., & Hastie, R. (2015). Wiser: Getting beyond groupthink to make groups smarter. Harvard Business Review Press.
Tetlock, P. E. (2005). Expert political judgment: How good is it? How can we know? Princeton University Press.
Tetlock, P. E., & Gardner, D. (2015). Superforecasting: The art and science of prediction. Crown.
Tversky, A., & Kahneman, D. (1973). Availability: A heuristic for judging frequency and probability. Cognitive Psychology, 5(2), 207–232. https://doi.org/10.1016/0010-0285(73)90033-9
Tversky, A., & Kahneman, D. (1974). Judgment under uncertainty: Heuristics and biases. Science, 185(4157), 1124–1131. https://doi.org/10.1126/science.185.4157.1124
Tversky, A., & Kahneman, D. (1981). The framing of decisions and the psychology of choice. Science, 211(4481), 453–458. https://doi.org/10.1126/science.7455683
Vohs, K. D., Schmeichel, B. J., Lohmann, S., Gronau, Q. F., Finley, A. J., Ainsworth, S. E., Alquist, J. L., Baker, M. D., Brizi, A., Bunyi, A., Butschek, G. J., Campbell, C., Capaldi, J., Cau, C., Chambers, H., Chatzisarantis, N. L. D., Christensen, W. J., Clay, S. L., Curtis, J., … Albarracín, D. (2021). A multisite preregistered paradigmatic test of the ego-depletion effect. Psychological Science, 32(10), 1566–1581. https://doi.org/10.1177/0956797621989733
Vul, E., & Pashler, H. (2008). Measuring the crowd within: Probabilistic representations within individuals. Psychological Science, 19(7), 645–647. https://doi.org/10.1111/j.1467-9280.2008.02136.x
Weinshall-Margel, K., & Shapard, J. (2011). Overlooked factors in the analysis of parole decisions. Proceedings of the National Academy of Sciences, 108(42), E833. https://doi.org/10.1073/pnas.1110910108
Williamson, A. M., & Feyer, A.-M. (2000). Moderate sleep deprivation produces impairments in cognitive and motor performance equivalent to legally prescribed levels of alcohol intoxication. Occupational and Environmental Medicine, 57(10), 649–655. https://doi.org/10.1136/oem.57.10.649
Videos
Galef, J. (2016, August 8). Why you think you're right, even if you're wrong [Video]. TED. https://www.youtube.com/watch?v=w4RLfVxTGH4
Heffernan, M. (2012, August 6). Dare to disagree [Video]. TED. https://www.youtube.com/watch?v=PY_kd46RfVE
Levitin, D. (2015, November 23). How to stay calm when you know you'll be stressed [Video]. TED. https://www.youtube.com/watch?v=8jPQjjsBbIc
Sharot, T. (2012, May 14). The optimism bias [Video]. TED. https://www.youtube.com/watch?v=B8rmi95pYL0