The singer revealed that the Fab Four met on a couple of occasions to talk about a reunion when they were all alive, but decided against it for fear of ruining their legacy.
McCartney told Rolling Stone: "There was talk of reforming The Beatles a couple of times, but it didn't gel, there was not enough passion behind the idea.
"More importantly, it could have spoiled the whole idea of The Beatles, so wrong that they'd be like, 'Oh, my God, they weren't any good'."
He added: "The reformation suggestions were never convincing enough.
"They were kind of nice when they happened – 'That would be good, yeah' – but then one of us would always not fancy it. And that was enough, because we were the ultimate democracy."
McCartney reached number three on the UK chart and number five on the US Billboard 200 with his latest album Kisses On The Bottom.
> Paul McCartney becomes final Beatle to join Hollywood Walk of Fame
Watch a preview of Paul McCartney's Kisses On The Bottom below: