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

On April 19, 1995, a man robbed two Pittsburgh banks in broad daylight. And strangely, the robber didn’t wear a mask.

A tip led police to a man named McArthur Wheeler, and when they knocked on his door, Wheeler was stunned. And 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.⁠

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 — a systematic error in thinking. Cognitive Biases work as mental shortcuts for making decisions, and everyone is susceptible to them, no matter their age, gender, or cultural background — they’re just a quirk of human behavior.

Our brains need to take in an incredible amount of information, but it also wants to save as much thinking energy as possible. So, it relies on generalities or rules of thumb (also called heuristics) to help it make hard decisions fast.

We rely on cognitive biases when we’re emotional, rushed to decide, or feel social pressure to make a choice. But everyday thinking and decision-making are subject to cognitive biases as well.

Source: Adobe Stock

How to Recognize the Dunning-Kruger Effect

While it can be difficult to recognize when someone is experiencing the Dunning-Kruger effect, here are a few common clues:

  • The person will not be open to criticism or help. They’ll see these as personal attacks or threats to their ego.
  • Victims of Dunning-Kruger are often very confident in their ability to do the task. Confidence isn’t usually a bad thing, but overconfidence can signal that someone “doesn’t know what they don’t know.”

You can commonly spot this effect in professional environments. You’ll notice that victims of Dunning-Kruger are difficult to work with and believe they always have killer ideas. Ambitious, competitive folks can be some of the worst offenders.

For example, imagine you work with an assistant marketing manager who comes up with an idea for a campaign. They think this idea is a winner and no one can change their mind — they might receive some expert suggestions on how to improve the campaign, but instead of thoughtfully considering these points they get offended. It’s possible that their confidence has outweighed their skills.

An internal Uber study even found that many new drivers practice an “extreme form of income targeting.” But as drivers got more experience on the platform, they found that income targeting behavior was inefficient because they’d have to work extremely long shifts on slow days and then get off early when they were busy.

In other words, by creating these arbitrary income goals to keep drivers driving, Uber was asking them to do something that experience would show was not actually in their best interest.

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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

Incompetent people who overestimate their ability rarely keep practicing and learning. They already believe they have a higher level of knowledge on the subject matter, so why waste time learning more?

But when you’re always learning and practicing a skill, you’re less likely to overestimate your abilities because you‘re always improving. Instead, you’ll be more aware of your own limitations and understand how far you have to go until you’re an expert.


2. Ask for Feedback

The second strategy is to get feedback from others. It’s hard to spot areas of improvement yourself because it’s not easy to see your skills objectively.

By getting feedback from trusted experts and friends, you’ll be able to identify areas for improvement without being blinded by your own ego.


3. Challenge What You Know

The third strategy is to challenge what you know. The best way to avoid the Dunning-Kruger Effect is by taking the time to challenge your own thinking and assumptions (as well as de-bias your thinking).

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