Ever since Taylor Swift's back catalogue re-appeared on Spotify last year - on the same day as arch-rival Katy Perry's new album was released, no less - there have been various conspiracies and think-pieces about what made her change her mind.

Now, however, Spotify boss Daniel Ek has revealed the truth - and basically it's that she just needed a bit of convincing.

He appeared on CBS This Morning - primarily to discuss Spotify going public and trading on the New York Stock Exchange - but touched upon Swift's 180-turn last year.

"I went to Nashville many, many times to talk to her team, spent more time explaining the model, why streaming mattered," he said. "And the great news is I think she saw how streaming was growing.”

He added: “I think she saw the fans were asking for it. So eventually when the new album came out, she came to Stockholm and spent some time there, figuring out a way that made sense for her.”

Swift currently has 26 million monthly listeners on the service.