Simon Cowell scaled back his work because he was "terrified" of suffering from "burn-out".
The 62-year-old music mogul decided to concentrate on being on TV rather than get involved with as much work behind the scenes, because it was "becoming too much", and he was keen to spend more time with his eight-year-old son Eric, who he shares with fiancée Lauren Silverman, 44.
He said: "I made the decision that my main job would be being on TV, not running a production company. It was just all becoming too much. And, if I’m being honest, I was very nervous about burn-out. I wasn’t feeling ill, I was just terrified that would happen to me.
"I’m a great believer in doing something before something bad happens, rather than waiting for something bad to happen.
"I was thinking a lot about that during the last two years. I’ve seen it happen to people, close friends of mine, where they get burnt out and you don’t want to be in that place. There’s no coming back from that.
"I wanted to spend more time with Eric - you only get this age once. Being able to pick him up from school every day, have dinner with him every night, all that kind of stuff, I’m able to do that now.
"He’s really a sweet little boy and I love him to death."
Simon - who broke his back after coming off his electric bike in Los Angeles two years ago, and then broke his arm in an e-bike accident in February - admitted the coronavirus pandemic inspired him to put his "health first".
He said: "Genuinely, because of COVID, it had such an impact on everyone and what I took away from it was you have to put your health first.
"You literally have to make it your number one priority."
Simon popped the question to Lauren on holiday in Barbados last year, and he is hoping there won't be too much stress planning their nuptials.
Speaking on US TV show 'Extra', he added: "Weddings themselves can be tricky. Everyone falls out, gets drunk and regrets what they say. The whole lead-up is stressful.
"It should just be, you know, whatever."