A new Taylor Swift interview in Vanity Fair offers some interesting background on the pop star's brief confrontation with Apple over artist royalties. Swift says she wrote the letter that made global headlines (and briefly put Apple in an unwanted spotlight) at 4AM. "The contracts had just gone out to my friends, and one of them sent me a screenshot of one of them," she told Vanity Fair. "I read the term ‘zero percent compensation to rights holders.’ Sometimes I’ll wake up in the middle of the night and I’ll write a song and I can’t sleep until I finish it, and it was like that with the letter."

That letter, published on June 21st in the form of a Tumblr post, described Apple Music's initial artist terms as "shocking" and "disappointing." Apple originally planned to withhold royalties for any streams during the service's lengthy three-month free trial, trying to sell the idea that higher payments later on would compensate. But Swift and many other artists were unconvinced. "Three months is a long time to go unpaid, and it is unfair to ask anyone to work for nothing," Swift wrote in June. The letter led to a stunning and almost instant reversal for Apple, with vice president Eddy Cue responding to Swift's frustrations later that day and pledging that Apple would in fact pay artists during the trial.

The quick response impressed Swift, who later gave Apple permission to stream her latest album, 1989. That deal is technically non-exclusive, but so far the hugely successful album hasn't appeared on rival services like Spotify, Google Music, or Tidal. "Apple treated me like I was a voice of a creative community that they actually cared about," Swift said. "And I found it really ironic that the multi-billion-dollar company reacted to criticism with humility, and the start-up with no cash flow reacted to criticism like a corporate machine."

That brutal quote suggests that Swift still isn't a fan of Spotify, though it's unclear how a company that loses more and more money with greater success was supposed to respond. If Spotify wants to rebuild any kind of relationship with Swift, the only option may be abandoning its free streaming tier altogether. In the aftermath of Swift's exodus from its service, Spotify has tried to emphasize the billions it has paid out to artists.

Swift also told Vanity Fair that the letter was read — or heard — by one person before it went live: her mother. "I read it to my mom," she said. "She’s always going to be the one. I just said, ‘I’m really scared of this letter, but I had to write it. I might not post it, but I had to say it.’" Scott Borchetta, chief executive of Swift's record label Big Machine, previously revealed that he didn't get any heads up on Swift's plan to call out Apple.

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