In a Songfacts interview, producer Carl Sturken gave details about the origin of the song:

We’d been working very closely with Rihanna and were in the process of recording songs for her third album. I was literally sitting on the front step of my house, getting ready to drive to the studio, and the title just came to me. I thought, ‘That’s pretty cool. OK, what do we do with that?’
So I came down to the studio and told Evan I had an idea. I started putting together a little sort of beat, and I knew that at a certain part of the chorus he’d want to sing that title. And that’s really all I had.
The music, when we first started out, was sort of like “The Glamorous Life” by Sheila E. That’s sort of where the beat was coming from. I was imagining doing something along those lines, and also, Fergie had a song called “Glamorous” with a similar vibe. It was the Fergie song I was sort of thinking about, but Evan said, ‘No, we should rock it out, man.’ Because he knew from talking to Rihanna that she wanted to do a rock song, or something more rockish. So I started putting the chords together, and the lyrics were really easy to write because the minute we started thinking of the car metaphors, we could just go to town. You know, the Lamborghinis and the Ferraris, there’s no end to things you can write, so that was like shooting fish in a barrel.
We recorded it in Barbados over the holidays because there was just no time to record in those days – she was running around the world.
When she heard it, she got super excited. Like, ‘Oh my God, I can’t believe you guys wrote this for me.’ Because no one else was doing anything like that for her.