The intelligent student at University assumes everyone is as intelligent as s/he is. They sit an exam, they can’t know how well they did, after all, they are learning a subject. They could be wrong.
When the intelligent student is told that s/he has scored in the top ten of the class, they gain the confidence and confirmation that their understanding of the subject is correct.
The stupid student assumes s/he is smarter than everyone else. They sit an exam assume they aced it. After all, they know everything.
When told they have scored in the bottom ten of the class, they disbelieve it. They never doubt themselves, never think they are wrong, and can find excuses because they ‘know’ they are brilliant.
They can make fools of themselves every day, yet, never see reality.