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?"