The Dunning-Kruger Effect
The Dunning-Kruger effect is a cognitive bias in which people wrongly overestimate their knowledge or ability in a specific area. This tends to occur because a lack of self-awareness prevents them from accurately assessing their own skills.
The concept of the Dunning-Kruger effect is based on a 1999 paper by Cornell University psychologists David Dunning and Justin Kruger. The pair tested participants on their logic, grammar, and sense of humor, and found that those who performed in the bottom quartile rated their skills far above average. For example, those in the 12th percentile self-rated their expertise to be, on average, in the 62nd percentile.
The researchers attributed the trend to a problem of metacognition—the ability to analyze one’s own thoughts or performance. “Those with limited knowledge in a domain suffer a dual burden: Not only do they reach mistaken conclusions and make regrettable errors, but their incompetence robs them of the ability to realize it,” they wrote.
Etc. Do read it all. Especially the final part where you learn how to avoid falling into the dilettante trap.