Before Adele's '25' was released, there was a lot of talk about the people she was allegedly working with - like Damon Albarn and Phil Collins, for example.

Albarn later came out and called the album 'middle of the road' and that he didn't expect what they worked on together to be used on the album's tracklisting.

Now, speaking to Billboard, Collins has revealed what really happened and why their collaboration didn't work out. 

"She sent me a piece of music that I began working on, but then she was very difficult to find," he said. "She had a kid -- all this [personal] stuff was happening to her, unbeknownst to me. I sent her an email asking, "Am I waiting for you, or are you waiting for me?" I found out she's a bit of a ghost -- Ryan Tedder told me that. You may not hear from her for a while. So nothing came of it."

He added: "I was very pleased to hear [it], because she's being asked about this with the release of her new album, that she said, "It was too early, and I was too scared." That's better than "He was terrible." I was very grateful for her gentle way of looking at it."