Pete Waterman thinks Simon Cowell knows "very little" about music.
The '80s record producer referred to the 'The X Factor' boss as a money making machine with no interest in real talent.
The 68-year-old told Daily Mail's Event magazine: "Simon knows very little about music. His knowledge comes out of the 'Guinness Book of Hits'. He'd keep a copy on his desk, and whenever an act came in he'd skim it for an old number one, look at the sales figures and then do it again.
"I love Simon he's the smartest man I know, but he isn't in it for the music."
He also labelled One Direction - who the music mogul looks after - as "the greatest marketing phenomenon ever".
He told the British magazine: "One Direction is a band but it sure as hell ain't anything to do with music.They are the greatest marketing phenomenon ever. Go and see one of their concerts - they are an eye-opener. It's all about sending tweets and talking to the crowd. You don't come out humming the tunes. All One Direction do is prove that Simon Cowell is a genius when it comes to making money. They are worth millions."
The former 'Pop Idol' judge added: "But imagine for a moment if they really could sing, really did write great songs - they would be worth squillions."
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