Dunning–Kruger effect

Incompetence often includes being unable to tell the difference between competence and incompetence. For this reason, it is difficult for the incompetent to recognize their incompetence.

The Dunning–Kruger effect is a cognitive bias in which people with limited competence in a particular domain overestimate their abilities. 

A Reddit post for reference. Memes are worth a thousand words.

Worth a read 📖 and I bet you can't help but think of a person or two around you and have a ‘aha’ moment. 

https://en.m.wikipedia.org/wiki/Dunning%E2%80%93Kruger_effect