experience is the teacher of fools

Foolish people only learn from personal experience, rather than witnessing others' mistakes. After watching Alex's failed attempt at the experiment, I realized what we were doing wrong. Experience is the teacher of fools.

Experience is the teacher of fools.

Prov. Only fools do not learn after seeing other people's mistakes and insist on repeating them. Father: You should spend more time studying and less time having fun with your friends. If I had been a better student when I was your age, I'd have a better job now. Son: Oh, come on, Dad. School's worthless. Father: Don't make the same mistake I did! Experience is the teacher of fools.