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Unskilled and Unaware: What is the Dunning-Kruger Effect?

Jennifer Clinehens

minute read

Quick Definition: The Dunning-Kruger Effect says that people who are unskilled at a task — often because they’re new at it — are overly positive when asked to evaluate those skills. 

The Dunning-Kruger effect is a psychological phenomenon inspired by a man named McArthur Wheeler, who robbed two banks in broad daylight without wearing a mask. 

On April 19, 1995, he walked up to two Pittsburg-area banks in broad daylight demanding the tellers give him cash. A tip led police to McArthur Wheeler, who was stunned when police found him. He kept repeating one curious phrase:

“But I wore the juice!”

When the police asked him what he meant, Wheeler told the officers he had rubbed lemon juice on his face so it would be invisible to the security cameras.⁠ He wasn’t delusional. Wheeler had just made a big mistake. You see, lemon juice can be used as invisible ink.⁠ Wheeler knew this and assumed that lemon juice could also make his face invisible to security cameras. He even tested it out by rubbing lemon juice on his face and taking an instant photo — which came out blank (probably due to user error).

Wheeler’s story caught the eye of a professor named David Dunning, who recognized the universality of Wheeler’s mistake: that people with the fewest skills and least knowledge often overestimate their abilities.⁠

This inspired observation became the basis of the Dunning-Kruger Effect.⁠

What Is the Dunning-Kruger Effect?

Coined by psychologists David Dunning and Justin Kruger, the Dunning-Kruger Effect says that people who are unskilled at a task — often because they’re new at it — are overly positive when asked to evaluate those skills.

Although inspired by McArthur Wheeler’s story, the official principle was based on a series of experiments published in the Journal of Personality and Social Psychology.

Dunning and Kruger concluded that people fail to recognize their own incompetence because they lack the skills needed to recognize it. Think about someone who’s never ice skated before — they take lessons for a few months and suddenly they’re an expert. But really, they don’t have practice or experience. They‘ve experienced some skating and have learned some fancy moves, but they don’t yet know what they don’t know.

Dunning-Kruger is a Type of Cognitive Bias

The Dunning-Kruger effect is a type of cognitive bias, which is a systematic error in thinking that affects decision-making. Cognitive biases work as mental shortcuts, allowing the brain to make fast decisions while conserving thinking energy.

Our brains receive an incredible amount of information, and they rely on generalities or rules of thumb, also known as heuristics, to help them make tough decisions quickly. Cognitive biases are not limited by age, gender, or cultural background, and we rely on them when we feel emotional, rushed, or pressured to make a choice. Even in everyday thinking and decision-making, cognitive biases can affect our judgment.

Source: Adobe Stock

How to Recognize the Dunning-Kruger Effect

Identifying the Dunning-Kruger effect can be challenging, but there are several telltale signs.

  • People who experience this effect tend to be resistant to criticism and help, often perceiving them as personal attacks or threats to their ego. 
  • Victims of the Dunning-Kruger effect typically exhibit an excessive level of confidence in their ability to perform a task, which can be a red flag for those around them. 

This effect is commonly observed in professional settings, where people with the Dunning-Kruger effect tend to be difficult to work with and believe they always have excellent ideas. Ambitious and competitive individuals may be some of the worst offenders. 

For instance, consider an assistant marketing manager who thinks their campaign idea is flawless and cannot be improved. Even after receiving feedback from experts on how to improve the campaign, they may become defensive or offended, indicating that their confidence outweighs their skills.

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3 Ways to Avoid the Dunning-Kruger Effect

There are three simple strategies you can use to help avoid the Dunning-Kruger Effect. They simply require you to open your mind to the idea that you might be falling into this thinking trap.

1. Keep Practicing and Learning

Individuals who overestimate their abilities usually fail to continue learning and practicing a skill since they already believe they know enough. However, consistent practice and learning can help one avoid overestimating their abilities and realize their limitations, leading to gradual improvement.

2. Ask for Feedback From Others

One may find it challenging to recognize their areas of improvement since they may not view their skills objectively. By seeking feedback from trusted individuals, one can receive an unbiased perspective on their skills and identify areas for improvement without being influenced by their ego.

3. Challenge Yourself

Challenging your own thinking and assumptions is the best way to prevent the Dunning-Kruger Effect. Taking the time to reflect on one's beliefs, biases, and thought processes can help identify flaws in thinking and decision-making. It allows individuals to understand the limits of their knowledge and expertise, leading to improved performance and decision-making.

 If you enjoyed this article, check out my podcast episode about the Dunning-Kruger Effect: 


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