Why are some people are incompetent

Incompetent people lack the skills to improve because they are unable to distinguish between incompetence and competence. Incompetent people overestimate their own competence and, failing to sense of mismatch between their performance and what is desirable, see no need to try to improve. Incompetent people can be taught to raise their competence by learning the skills to judge their own performance more accurately.

To become more competent, or even expert, we must learn to recognize competence when we see it in others, become more accurate judges of what we ourselves know and don't know, adopt learning strategies that get results, and find objective ways to track our progress.

Peter C. Brown and Henry L. Roediger III, Make It Stick: The Science of Successful Learning