Why do we believe we are good at something when we actually aren’t?


Dunning–Kruger Effect

, explained.

What is the Dunning-Kruger Effect?

The Dunning-Kruger effect describes people who perform a certain task poorly while simultaneously overestimating their ability and knowledge in the relevant area.

Availability Heuristic

Where this bias occurs

Think back to primary school. We all knew someone who thought they were more intelligent than they really were. Let’s call this person ‘John.’ Even though John is normally well below the class average in school assessments, he also raises his hand to speak far more than average in the classroom. John has unshakable confidence in his knowledge of history, science, and literature, insisting to his friends that his poor marks are simply a reflection of bad testing methods and his “not caring.” Still, it is abundantly clear to the teacher and his fellow classmates that John has no idea what he’s talking about. John consistently decides to raise his hand to speak on matters he is unfamiliar with. John’s inability to recognize his incompetence, and the resulting overconfidence, is what is known as the Dunning-Kruger effect.

Individual effects

The Dunning-Kruger effect can lead us to make poor decisions in our personal and professional lives. It is no mystery that competence in a certain area improves decision-making in that sphere. As our understanding of a topic, or experience with a task, increases, we become better at identifying good decisions from bad ones in those areas. Past success causes us to become confident in our ability because we foresee a high probability of future success. This is not usually a problem because our actual and perceived ability are relatively equal, which makes our probability calculations fairly sound.

However, when we think that we are better at something than we really are, a gap emerges between perceived and actual ability. This gap — or, over-evaluation of our actual ability — is problematic because it makes us believe there is a greater chance that our decisions will be good ones than is truly the case. This can explain why show contestants choose to subject themselves to what usually turns out to be public humiliation. They are unaware of their inability to sing, which causes them to be confident in their ability to sing — until they are rejected by the judges.1

People who are affected by the Dunning-Kruger effect are also less able to learn from their mistakes. Their self-confidence makes them biased self-evaluators, and so they have difficulty identifying their bad decisions, as just that: bad. This is an issue, as we learn to make better decisions by looking back at the mistakes and successes of our previous ones.

Systemic effects

Decisions that are motivated by the Dunning-Kruger effect can multiply to create systemic problems. The primary challenge is that it may prevent expertise from reaching the decision-making table. In other words, it can prevent people who truly are proficient in a task or topic, from making the decisions in the relevant area of expertise.

Often the loudest person in the room gets the most attention and takes over the discussion. With regard to the previous example, John’s tendency to express uninformed views likely prevents other students with more fruitful points from participating. This phenomenon may also affect larger organizations, in which the most capable people do not always make the decisions; instead, those with the greatest perceived ability take precedence. The latter takes the place of the former, which, clearly, is sub-optimal.

Why it happens

As said earlier, the Dunning-Kruger effect arises from a gap between perceived and actual competence. But why does this gap emerge?

The two-pronged problem

When we lack expertise and skill in an area, we often perform poorly as a result. The second part of the problem is that the deficiencies that lead to poor performance also make us unable to recognize it. How can you know that you are bad at something if you don’t have the tools to recognize your incompetence? Imagine trying to pick out a well-written book if you yourself do not have good grammar.

It is therefore the same skills and knowledge that are necessary to be good at something a person needs to realize they are not good at it. This means that if a person does not have those abilities, they are not only inept but unaware of their own inability.2 Dunning and Kruger call this the “dual burden.” As a result of the dual burden, many of us are unable to accurately assess our own abilities in some areas.

“Overestimation occurs, in part, because people who are unskilled in these domains suffer a dual burden: Not only do these people reach erroneous conclusions and make unfortunate choices, but their incompetence robs them of the metacognitive ability to realize it.” – Dunning and Kruger

We can’t look at ourselves from the outside

Many people struggle with “metacognition”, which describes someone’s awareness of their own thinking and behaviour. For our purposes, it is our ability (or lack thereof) to step back and consider ourselves from an outside perspective. Doing this is often difficult, as most of us are accustomed to seeing the world, and ourselves, through our own eyes. Yet, from this ‘subjective’ point of view, we often consider ourselves to be highly skilled and knowledgeable. As a result, we often have difficulties recognizing a more realistic view of our own abilities.3 This makes sense: when we are grumpy or inconsiderate, it often takes a friend or family member to call us out. A lot of the time, we lack the self-awareness to notice about ourselves what we so easily notice about others.

This lack of ‘metacognition’ might also be related to our brain’s use of ‘heuristics.’ These are mental shortcuts we use to make decisions efficiently. Thinking about and questioning yourself takes time and energy. So, assumptions about our competence in certain situations could be a shortcut to solving them quickly.

We like to feel good about ourselves

Another reason why we sometimes experience the Dunning-Kruger effect is that it protects our self-esteem. No one likes feeling bad about themselves — and realizing that we are bad at something can have this effect because it may suggest that we lack intelligence. As a result, we often don’t want to plead ignorance to others or ourselves.

This response can be conscious or subconscious. It has been suggested that our mind creates a natural defense to respond in this way to these situations that we can be unaware of.4 This may be why we tend to overestimate our abilities and knowledge on various topics.

“Poor performers—and we are all poor performers at some things—fail to see the flaws in their thinking or the answers they lack. When we think we are at our best is sometimes when we are at our objective worst.” – Dunning and Kruger

Why it is important

That being said, we should be aware of the Dunning-Kruger effect because of the negative influence it can have over our decision-making. When someone doesn’t have the tools (ie. experience or cognitive capacity) to make an informed decision, they often don’t make it because of the high likelihood that it will have adverse consequences. But if someone is unaware of their shortcomings, they make such decisions irrespective of the negative implications they will likely have. Moreover, because people subjected to the Dunning-Kruger effect are confident in their abilities, significant resources and energy can be invested in the success they believe that poorly informed decision will bring. This is less than ideal at best and dangerous at worst.

Consider the scenario in which a young driver is so confident in their driving abilities that they decide to go on the highway in the midst of a dangerous snowstorm. Or, in a professional setting, think of an executive who boldly invests in the promotion of a product which they don’t understand.

It is also worth noting that overconfidence usually does not bode well with others– especially if it is misplaced. ‘Arrogant’ is a label worth avoiding.

How to avoid it

Dunning and Kruger suggest that the overestimation of our competence is greatest when we have a narrow understanding of a topic. Our confidence finds its lowest point when we have no understanding, but trails down from its mistaken peak when we gain a fuller understanding that reveals the gaps in our knowledge. Here, we display a lower, but more realistic level of confidence in our abilities. As we gain expertise, we also gain confidence — but now it is well placed. Indeed, experts should display a high degree of confidence in their ability because they usually truly are capable. This chart demonstrates the U-shaped relationship between confidence and competence that characterizes the Dunning-Kruger effect.

But what does this have to do with avoiding the potentially damaging implications of the Dunning-Kruger effect?

Well, if our perceived ability of a subject is brought inline with our actual ability through increased knowledge, then one strategy would seem to be deepening our understanding. Rather than assuming you know all there is to know about a topic, explore it further. As you have a better grasp on a subject, you will probably realize there is still much to learn. This can help counteract our habit of mistakenly thinking we’re experts when we aren’t.

Another strategy is to ask other people to evaluate your performance. Remember, we often struggle to consider ourselves from an outside


  1. Samson, A. (2017). The Behavioral Economics Guide 2017. Behavioral Science Solutions.
  2. Cherry, K. (2019, June 14). Dunning-Kruger Effect: Why Incompetent People Think They Are Superior. Retrieved June 26, 2020, from https://www.verywellmind.com/an-overview-of-the-dunning-kruger-effect-4160740
  3. Ehrlinger, J., Johnson, K., Banner, M., Dunning, D., & Kruger, J. (2008). Why the unskilled are unaware: Further explorations of (absent) self-insight among the incompetent. Organizational Behavior and Human Decision Processes,105(1), 98-121. doi:10.1016/j.obhdp.2007.05.002
  4. Duignan, B. (2019, July 26). Dunning-Kruger effect. Retrieved June 26, 2020, from https://www.britannica.com/science/Dunning-Kruger-effect
  5. Crew, D. (2019, February 14). Start-and-Up: Dunning-Kruger effect on startups. Retrieved June 26, 2020, from https://medium.com/swlh/start-and-up-dunning-kruger-effect-on-startups-19c0aa921688
  6. Why Startups Fail: Top 20 Reasons. (2020, February 03). Retrieved June 26, 2020, from https://www.cbinsights.com/research/startup-failure-reasons-top/