The Dunning-Kruger effect is a product of our subjective understanding of the world. It serves as a caution against assuming we’re always right.
When you actually know about something you are usually alert to how much you don’t know. You leave your mind open to possibles because you know you don’t have all the answers.
Stupid people might know nothing about a topic. Maybe they saw some story on Facebook, or someone told them something. As they don’t have the capacity to research, as they don’t have the knowledge to know how much they don’t know, they can be certain.
As they are certain of themselves, they make absolute fools of themselves. They do not have the capacity to step back, analyse, see they are wrong, and see how they are wrong.
They will persist in their stupidity looking for other reasons or possibilities as to why something failed.
The simple point is, stupid people never learn.
If you don’t want to be stupid, never overestimate yourself, your knowledge, your ability. Always recognise you don’t know everything