Nikki Sixx isn't pulling any punches about why Mötley Crüe decided to call it quits.

In a new interview with Classic Rock, Sixx promised that the band's final interviews — recorded the night of what was billed as their last-ever show, and due for release as part of an upcoming concert film — include some frank talk regarding the reasons for their farewell tour.

"We talk about each other in a way that’s endearing – but not," said Sixx. "We say where we’re really at. We talk about the drama and the pain of being in a band that has ceased to run on creativity, just on pure, mechanical motions."

The band's dormant creative spark spurred Sixx to refuse to write new material for the soundtrack to the upcoming film adaptation of their The Dirt memoir. "If it comes down to, ‘Well, you have a movie, you need to write music,’ I’m like, ‘Sorry, but that’s cheap. We don’t want to go, ‘We have to write a song for marketing,'" he explained. "I want to write music because it’s real. There’s not a relationship there. Let it die gracefully. We couldn’t be creative as a band, so how the hell can we continue?"

Sixx also doubled down on his previous promise to never perform Crüe songs with his current band, Sixx:A.M. — or as part of any other project, for that matter. "I want to just leave it intact. We said what we had to say. I’m proud of what we did – I don’t want to disgrace it by being cheap."

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