Simon Cowell Can’t “Wait” to Leave American Idol

 Michael Rozman/Warner Bros.

Simon Cowell won't be too bummed after he steps away from the American Idol judge's table for the last time after Wednesday night's finale.

"I am feeling a bit sad because we're nearly there, but at the same time… do you remember, sort of, those last three weeks when you were leaving school and you kind of couldn't wait to get out?" Cowell says on The Ellen DeGeneres Show Wednesday.

PHOTOS: Before they were Idol judges

"It's a little bit like that. It's kind of exciting. I'm not being ungrateful," adds Cowell, 50.

Continued Cowell, who will launch an American version of the X-Factor in 2011, "I am feeling a bit sad because I've had a fantastic time and the show changed my life but I just kind of knew it was time to do something different."

VIDEO: Relive this season's WORST Idol auditions

One thing the prickly judge regrets: Quitting on DeGeneres' first day. "I do actually feel guilty about that. I genuinely do because I didn't think about that… two hours before you're starting, I held a press conference to say, 'By the way I'm leaving.' Nice way for you to start…."

Cowel thinks Lee DeWyze win the show.

PHOTOS: Look back on this year's Top 12

"If you'd of asked me five or six weeks ago, 100 percent I would have said Crystal [Bowersox]," Cowell says. "But now I've changed my mind."

"The last two years, I've gotten it completely and utterly wrong, so I don't think anyone is listening to me anymore," he goes on. "But it's just a hunch. Something about him… He's worked in a paint shop. He's talented. He hasn't had any real breaks in life and this has given him a shot and I like that."

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