R.E.M. Broke Up to 'Walk Away as Friends,' Releasing Greatest Hits in November

Following last week's surprise announcement that R.E.M. were breaking up, the band has opened up about why it decided to suddenly call it quits after 31 years.

"It's not because we have to or we can't stand each other or we suck," bassist Mike Mills said in an interview with Rolling Stone's David Fricke. "We're happy. But we're done."

Mills also revealed that the band, which also includes singer Michael Stipe and guitarist Peter Buck, had discussed the end as far back as 2008: "We'd say things like, 'We have X number of records in the contract. By the time we finish, we'll be X number of years old. Do we still want to be out there flogging it?'"

So why wait to walk away after releasing their 15th album, 'Collapse Into Now,' in March? As Mills revealed, the band wanted to prove that it could still put out worthwhile material, especially following 2004's poorly received 'Around the Sun.'

"We needed to prove, not only to our fans and critics but to ourselves, that we could still make great records, and we made two," he said, referring to 'Collapse' and 2008's 'Accelerate.' "We thought, 'We've done it. Now let's do something no other band has done: Shake hands and walk away as friends.'"

Fans won't have to wait long to hear R.E.M.'s final recordings. The group will release three new tracks on their upcoming hits compilation, 'Part Lies, Part Heart, Part Truth, Part Garbage: 1982-2011.' The record is due out from Warner on Nov. 15, with 'A Month of Saturdays,' 'We All Go Back to Where We Belong' and 'Hallelujah' rounding out the 40-song double album.