Andrew Garfield felt "worthless" at school.
The '99 Homes' actor - who is dating Emma Stone - was "lost" as a teenager because he didn't want to follow an academic path, but found his calling when he appeared in a play for the first time.
He said: "I was quite lost as a teenager as I didn't really get along with the school system where all that was valued was academia.
"You were supposed to want to be a doctor or a lawyer or a businessman or you were regarded as worthless, so I didn't really fit in anywhere.
"And then I did a school play and suddenly felt a sense of joy and purpose - my whole body went 'Oh - I've arrived somewhere that feels like part of me and this is going to be part of my life.' "
The 32-year-old actor thinks anyone can be a success, no matter what career path they take, so long as they stay true to themselves.
He told HELLO! magazine: "To my mind, real success means being true to yourself.
"You might be an actor or a musician or a doctor or a lawyer - or you might be a waiter and make really great coffee.
"I think the work of all our lives is to find what we are supposed to do with ourselves and do it well and with pride."