It's called the Dunning-Kruger effect. Interesting read.
Are you incompetent? You might never know.
WikipediaThe Dunning–Kruger effect is a cognitive bias in which people with low ability at a task overestimate their ability. It is related to the cognitive bias of illusory superiority and comes from people's inability to recognize their lack of ability. Without the self-awareness of metacognition, people cannot objectively evaluate their level of competence.
https://en.wikipedia.org/wiki/Dunning%E2%80%93Kruger_effect