Simon Cowell steps in to replace Howard Stern on NBC's America's Got Talent tonight (May 31), and he's far more excited about the new role than he was about some of his past projects toward the end.

Cowell spoke to the New York Times about returning to his role as star-maker in a performance competition — a genre he helped popularize in America as an original American Idol judge before going on to create The X Factor and the international Got Talent franchise. But the SYCO label head walked away from Idol in 2010, and by the time it wrapped its final season this year, Cowell was no longer even a viewer.

"I completely lost interest in it, to be honest with you," Cowell told the Times, admitting he was a bit checked out in the final years of his tenure there.

"I was just bored. I had done nine seasons. The first three or four years were genuinely probably the best three or four years of my life," he said. "It was so much fun, so unexpected, we didn’t know what was going to happen, the show just took off and became a huge hit and we were in the middle of something that we were making up every week. Then it all started to get a bit serious and Paula [Abdul] left and then it just wasn’t the same to me." Paula really did add an oft-whimsical dimension to the panel — she had that "x factor," if you will.

Cowell also admits some missteps with the American incarnation of X Factor, which only lasted three seasons on Fox from 2011-2013. Pointing to the fact that he was used to the massive ratings of Idol in its heyday, he says disappointing numbers incited too many changes and hobbled the series.

"The show became unrecognizable," Cowell says. "I blame myself, but we made crazy decisions. We didn’t treat it like a hit. We treated it as a failure. I wasn’t aware the market had gone down to that level so quickly. I was in this La-La Land head space of 30 or 40 million and I thought 12 million feels terrible."

Of course, the U.S. version did spawn one big act — third-place finishers Fifth Harmony — so we would never call the show a total failure.

And just because Cowell's settling into a new judges' chair doesn't mean he's not hatching a plan for the next big thing in competitive TV. Drawing upon what he's learned, including the fact that singing show seasons are "too long" and "people love auditions," he says he won't give too much away now but the "idea is unique." So look for America's Next Superstar Auditioner in 2017, then?

To find out what Simon has to say about The Voice, and whether he thinks his opinionated judge archetype helped usher Donald Trump to bigger fame, check out the full interview over at the NY Times.

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