Britney Spears Leaving 'X Factor'

Frank Micelotta / FOX

It seems the great X Factor experiment is over.

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Sources tell The Hollywood Reporter that Britney Spears is destined to be a one-term judge on the Fox show. Although no official word has been handed down by execs to the talent (creator Simon Cowell, for one, still is on holiday somewhere off the coast of St. Barts), an X Factor insider says the writing was on the wall: Spears was not going to be asked back and will not return for season three.

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Blame the double-digit dip in ratings and a case of mismanaged expectations for her anticipated exit, which TMZ first reported with the headline, “I Quit, Y’All!” By several accounts, her performance on the live shows simply underwhelmed, and the constant criticism -- especially from the media, both traditional and social -- was starting to bother the shows top brass. Spears' deal with X Factor brought her about $15 million, THR had previously reported.

Fox had no comment. The network already has given the green light to season three, and at Tuesday’s executive session at the Television Critics Association gathering in Pasadena, Fox entertainment chairman Kevin Reilly complimented Spears on her performance. "I think Britney did a really good job," he told reporters, adding that he would like her to return. But he also acknowledged: “Maybe some people were waiting for more drastic displays of some nature that never came, so for those expecting that, it didn’t happen. … She’s just an interesting figure who's lived a unique life, and I thought she brought some of that."

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To be fair, Spears did have her moments -- like the time she told contestant CeCe Frey, "Sorry, I just don’t get it," without flinching (the song: self-pity anthem "All by Myself"). And who could forget her funny faces collage, stitched together for the finale? If only Spears could expand her vocabulary.

With L.A. Reid’s previously announced exit, that leaves two seats to fill next season -- and another judge hunt for Fox, Syco and production partners FremantleMedia to sludge through.

At TCA, Reilly noted that Cowell "hasn’t even talked about any of this going forward." Indeed, it looks like this wheel is grinding to a halt, but Spears still has her lucrative music career. The singer is in the studio with will.i.am working on a new album.

Lacey Rose contributed to this report.