The secret of Dunning-Kruger effect:
Why the more ignorant you are, the more confident you are, and the more knowledgeable you are, the more humble you are.
The Dunning-Kruger effect, also known as the Duncan-Kruger effect, is a cognitive bias:
People with poor abilities often have an illusory sense of self-superiority, mistakenly believing that they are better than they actually are.
In short, people with poor abilities are prone to self-inflation due to a lack of self-knowledge.
