"I'll Wait" was written as a collaboration between the Van Halen group members and former Doobie Brother Michael McDonald. The singer was brought in by producer Ted Templeman, who had a long professional relationship with the Doobie Brothers. McDonald recalled to Uncut:
"Van Halen had cut the track - the chord progression and the arrangement was already recorded and they needed some lyrics and a melody to go over that. Ted asked me to help out, so I sat down with David Lee Roth in Ted's office at Warner Brothers and wrote out a lyric.
Just to show you the difference between that band and our band as far as record sales, I probably made more money as a one fifth writer on that song than I did on the entire Doobie Brothers album the subsequent year."
According to ClassicVanHalen.com, the synthesizer-driven song is about a girl wearing men's underwear in a Calvin Klein print media ad. Roth tacked the picture next to a Sony Trinitron TV and he and McDonald addressed the lyrics to her.
Randy from Las Vegas, NvI know this is just a personal anecdote but I was talking to a girl one night in an AOL chat room in 1994 and she told me she was friends with Christie Brinkley and she said Christie had a huge crush on David Lee Roth in the early 80's and even kinda stalked him LOL. She said Dave was also enamored with her and wrote this song about her. Like I said, it was just one conversation that I have no solid proof on but it seemed credible.