Simon Cowell "didn't learn anything" at school.
The 51-year-old music mogul - who has an estimated personal fortune of over £165 million - admits he was never academically successful but believes he has done well out of life because he has such good instincts.
He said: "All my life I had to teach myself. I never really had a proper education. I wasn't born with any skill. I didn't learn anything from school.
"Mainly, I trust my instincts because I have very broad tastes. I genuinely believe that if I like something, other people are going to like it as well."
Simon quit 'American Idol' last year in order to focus on bringing his UK show, 'The X Factor', to the US and admits it took a discussion with an unnamed "successful" friends to make him realise it was time to go.
He explained on a forthcoming episode of 'Oprah Presents Master Class': "I asked a very successful guy, 'What's the best advice you can give me?' and he said, 'Simon, always know when to leave the fair.' And I think that's good advice. Something inside you just says, 'You know what, it's time to go.' Without any regrets whatsoever."
Despite departing 'American Idol', Simon - who got engaged to make-up artist Mezhgan Hussainy last year - insists he has enjoyed being a TV talent show judge because it isn't very difficult.
He added: "I can look back on the past ten years and say, 'It's been a blast.' I've enjoyed myself, I mean it's not the most difficult job in the world is it?"Reuse content