What Is Hindsight Bias? | Definition & Examples

Hindsight bias is the tendency to perceive past events as more predictable than they actually were. Due to this, people think their judgement is better than it is. This can lead them to take unnecessary risks or judge others too harshly.

Example: Hindsight bias
Football fans often criticise or question the actions of players or coaches in what is known as ‘Monday morning quarterbacking’. They often claim they knew the result before the game was over and that the outcome was easily preventable. This is particularly the case after a loss.

However, it is easy to pass judgement from a position of hindsight and to recognise bad decisions after the fact. When you know the result, you know what worked and what didn’t work during the game. Hindsight bias is the reason behind the ‘Monday morning quarterback’ phenomenon.

Because people feel that they ‘knew it all along’, they overestimate their ability to foresee the outcome of future events, such as medical errors, sport scores, or election results.

What is hindsight bias?

Hindsight bias is a type of cognitive bias that causes people to convince themselves that a past event was predictable or inevitable. After an event, people often believe they knew the outcome of the event before it actually happened.

In reality, people usually consider many different scenarios of what might happen in the future, but there’s no way to be certain which one of them will ultimately materialise. Regardless of which scenario plays out, people become convinced that ‘they saw it coming’.

Hindsight bias is more likely to occur when the outcome of an event is negative rather than positive. This is consistent with the general tendency people have to pay more attention to negative outcomes of events, known as negativity bias.

Hindsight bias, for instance, might cause us to think that we ‘knew’ a couple in our social circle would break up. This is because our current knowledge allows us to easily re-interpret any past disagreements or questionable behavior as a sign of trouble.

Why does hindsight bias occur?

Hindsight bias occurs as a result of our effort to make sense of an outcome. During this process, we essentially ‘rewrite the story’, focusing on certain factors and disregarding others.

Three different processes are involved in hindsight bias (these can occur independently or together):

  • Memory distortion or ‘I said it would happen’. Memory distortion is the misrecollection of our earlier judgements. We often misremember past events or information in such a way that they agree with what we already know. This distorted recall also factors into confirmation bias and the availability heuristic. In other words, knowing the outcome makes that outcome more available to us, which means we overestimate how probable the outcome was in the first place.
  • Inevitability or ‘It had to happen’. This involves beliefs about how the world works and what caused an event. In general, people like to think that the world is an orderly place. We strive to maintain this idea of order by drawing on cause-and-effect relationships to explain events. With the information we have at the present moment, it’s easy to see an event as predetermined or inevitable, and this aligns well with how we like to view the world.
  • Foreseeability or ‘I knew it would happen’. This occurs when we retrospectively think that we were able to foresee or predict the end result (the ‘I-knew-it-all-along’ effect). It is easy to understand an event in retrospect, when all the information is available to us. Because it’s easy, we feel certain that we had this understanding all along. This part of hindsight bias relates to the availability heuristic.

What is the impact of hindsight bias?

Hindsight bias causes people to think that certain (negative) outcomes were far more predictable and avoidable than they were in reality. This can have both negative and positive consequences.

  • Hindsight bias can become a decision trap because it leads to a flawed assessment of the past. If we have a false idea about how accurately we predicted the outcome of past events, we become overconfident. This has implications for the quality of our future decisions.
  • Failure to be surprised by an event prevents us from learning from it. If we have the feeling that ‘we knew it all along’, it is unlikely that we will take the time to reflect and try to understand why our predictions at that time were wrong.
  • Hindsight bias will likely cause us to judge others unfairly for not having been able to foresee past events. This can lead us to criticise the quality of other people’s decisions in the past, using the information available to us at present.
  • However, hindsight bias can also work to our advantage. Studies have shown that the same sense-making process that produces hindsight bias can reduce the pain of negative emotional events. In other words, we can comfort ourselves by saying ‘I knew this would happen’.
  • Some studies propose that we may learn from hindsight bias without realising it. According to this view, hindsight bias is the consequence of our ability to update previously held knowledge. This is a necessary process in order to prevent memory overload and allow our brains to function. Updating allows us to keep our knowledge more coherent and to draw better inferences.

Hindsight bias examples

Entrepreneurs who don’t see their plans succeed often exhibit hindsight bias.

Example: Hindsight bias and startup failure
Studies have shown that entrepreneurs are highly susceptible to hindsight bias. In one study, researchers surveyed 705 entrepreneurs from failed startups. Before the failure, 77.3% of entrepreneurs believed their startup would grow into a successful business. However, after the startup failed, only 58% said they had originally believed their startup would be a success.

In other words, entrepreneurs tend to downplay their initial optimism and overestimate their ability to foresee the future. This systematic distortion of the past has important implications for future ventures. Due to hindsight bias, entrepreneurs are at risk of overestimating their chances of success when launching their next startup

In medical malpractice lawsuits, jurors need to factor in hindsight bias when deciding whether a doctor did the best they could with the knowledge they had at the time.

Example: Hindsight bias and medical errors
During a routine physical examination, a 68-year-old man undergoes a chest x-ray in a local community hospital. The radiologist who looks at the x-rays finds nothing out of the ordinary.

The man doesn’t visit his physician again until 4 years later, when he begins experiencing a cough, chest discomfort, and weight loss. The new x-ray shows a tumor which needs urgent treatment. The man decides to sue the first radiologist, who missed the tumor in the initial x-ray.

In court, the second radiologist argues that the first radiologist should have been able to see the tumor in the earlier x-ray.

The radiologist’s attorney, on the other hand, defends his client by claiming that the other radiologist only spotted the cancer because they already knew what to look for. In other words, the attorney claimed that hindsight bias was at play, and it was unreasonable to expect that the first radiologist should have known what was only knowable from an x-ray that came later.

How can we reduce hindsight bias

Hindsight bias is part of human nature, but there are steps you can take to reduce it:

  • First and foremost, acknowledge that we all have biases. Especially when you are thinking about the past, be aware that hindsight bias may influence your perception.
  • Track your thoughts regarding possible outcomes in a decision journal. Documenting what you expect to happen allows you to keep a record of what you were thinking at the time you made the decision. By reviewing it afterwards, you will be able to see how accurate your forecast was, but also where it went astray.
  • Use the ‘consider-the-opposite’ strategy. Avoid the urge to view past events as having been inevitable by examining all other possible outcomes. With this strategy, we are forced to consider how outcomes that did not occur could have occurred. Raising our awareness of other possible explanations and causal links is an effective debiasing technique.

Other types of research bias

Frequently asked questions

Why is hindsight bias a problem?

Hindsight bias is a problem because it causes us to unfairly criticize other people’s decisions and actions. It is easy to see why things unfolded the way they did in the past from the vantage point of the present, when all information is available to us.

Being more informed may cause us to erroneously think that a chain of events was inevitable or predictable. In addition to that, hindsight bias makes us overestimate our own ability to predict the future, which can result in bad or risky decisions.

What is a real-life example of hindsight bias?

An example of hindsight bias in real life is how easy a test might seem after we know the correct answers.

Suppose you are uncertain about the answer in a multiple choice test question. You are not sure if it’s A or B, but eventually you choose B. When the teacher mentions that the correct answer is indeed B, your first reaction might be “I knew it was B all along.” In other words, you might feel more confident about your knowledge after you hear the correct answer.

What is the difference between hindsight bias and confirmation bias?

Hindsight bias and confirmation bias are both types of cognitive bias and can distort our perception. Although they are related, they are distinct types of bias.

Hindsight bias refers to how knowing the outcome of a past event gives it a sense of predictability in the present, making it harder for us to consider other possible outcomes. In other words, it causes us to look at the past in a biased way due to knowledge or information that is only available to us in the present.

Confirmation bias refers to how our current values and beliefs function as a filter through which we select and recall information. If the information doesn’t align with what we already believe to be true, we simply dismiss it.

In other words, hindsight bias is a belief-updating process (we update past thoughts because of new information), while confirmation bias is a belief-alignment process (we select information that agrees with what we already think.)

Sources for this article

We strongly encourage students to use sources in their work. You can cite our article (APA Style) or take a deep dive into the articles below.

This Scribbr article

Nikolopoulou, K. (2023, February 10). What Is Hindsight Bias? | Definition & Examples. Scribbr. Retrieved 17 July 2024, from https://www.scribbr.co.uk/bias-in-research/the-hindsight-bias/


Cassar, G., & Craig, J. B. (2009). An investigation of hindsight bias in nascent venture activity. Journal of Business Venturing, 24(2), 149–164. https://doi.org/10.1016/j.jbusvent.2008.02.003

Groß, J., & Bayen, U. J. (2022). Older and younger adults’ hindsight bias after positive and negative outcomes. Memory & Cognition. https://doi.org/10.3758/s13421-021-01195-w

Pezzo, M. V. (2011). Hindsight Bias: A Primer for Motivational Researchers. Social and Personality Psychology Compass, 5(9), 665–678. https://doi.org/10.1111/j.1751-9004.2011.00381.x

Roese, N. J., & Vohs, K. D. (2012). Hindsight Bias. Perspectives on Psychological Science, 7(5), 411–426. https://doi.org/10.1177/1745691612454303

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Kassiani Nikolopoulou

Kassiani has an academic background in Communication, Bioeconomy and Circular Economy. As a former journalist she enjoys turning complex scientific information into easily accessible articles to help students. She specialises in writing about research methods and research bias.