Songfacts®:

• Running 7:42, "Once" is a slow build, built on a bed of piano and leading to an extended guitar solo by Eddie Van Halen. The lyric, written by their lead singer at the time, Gary Cherone, is of the introspective and inspirational variety, more a series of quotes than a cohesive story:
  
  Once seen, can't ever lose sight
  ...
  Holding the intangible
  To believe in a miracle
  
  Cherone likes the song, mentioning it among the best from his time with Van Halen. "Something that I thought was new and original was a song called 'Once,'" he told Songfacts. "I thought Eddie musically expanded his horizons. It started off as a piano piece, but then it got a little bit more elaborate with the band. Lyrically, I think it was a bit more complex."
• Van Halen made a video for "Once" that was posted on their official site. It was directed by David Bertinelli, Eddie Van Halen's brother-in-law. The video, comprised of concert and behind-the-scenes footage, didn't stay posted for long.
• The song is part of Van Halen III, the only album they made with Gary Cherone. He joined the group in 1996 after Sammy Hagar left and an attempt to reunite with David Lee Roth faltered. He was thrown into the songwriting fire right away. "I would have rather toured and then recorded the first record with them, because Van Halen III was a studio production, I was getting to know the guys, and there was a writing/evolutionary process of me and Eddie writing," he told Songfacts in 2023. "Then we went on tour and we became a band. We pretty much lived together on the bus and playing so many shows, so we came back tighter, we came back more focused."