Songfacts®:

• This upbeat retro-disco tune was written by Lady Gaga for the A Star is Born movie. In the film, Lady Gaga's aspiring singer character Ally performs the tune during her breakthrough appearance on Saturday Night Live.
• Lady Gaga wrote the song with:
  
  Her friend DJ White Shadow (Paul DJWS Blair), who has been collaborating with Gaga since her Born This Way album.
  
  Hitmaker Diane Warren, who previously teamed with Gaga for "Til It Happens To You," the end credits song of the documentary film The Hunting Ground.
• Though "Why Did You Do That?" appears halfway through A Star Is Born's narrative arc of Ally becoming a pop star, this was the first song that Gaga and DJ White Shadow wrote for the project. The pair then worked outwards on songs before and after the character's big TV debut. "We started with that motif and then worked our way around that, like, 'What's the song that sounds the most like when she's gonna break?' And then we worked outward from there," White Shadow told Genius. "I just think that seemed like a natural place to start for a girl that we knew was going to be famous."