Songfacts®:

• In June 2021, Blink-182 bassist Mark Hoppus announced he was undergoing treatment for diffuse large B-cell lymphoma, a type of non-Hodgkin lymphoma. He underwent chemotherapy and was declared cancer-free in September 2021.
  
  Hoppus has been open about his cancer journey and has used his platform to raise awareness about the disease. He penned the verses of this somber, reflective tune about his torrid time following his diagnosis.
• Hoppus recounts the fear that gripped him and his loved ones. He bares his soul about those "long weeks of impending doom" and being "stuck in life's waiting room," mirroring the hopelessness that shadowed his darkest hours.
  
  It was a life on hold, filled with despair. Yet, from the depths of his hopelessness, Hoppus found a profound truth: "You don't know what you've got till it's almost gone."
• The repeated "You don't know what you've got till it's almost gone" echoes the same sentiment in the title track of One More Time.... They both show how Hoppus' cancer scare was the jolt Blink-182 needed to truly appreciate one another.
• Blink-182 drummer Travis Barker produced "You Don't Know What You've Got." The three band members wrote the song with help from Barker's frequent collaborator Nick Long and songwriter Michael Pollack (Maroon 5's "Memories," Miley Cyrus' "Flowers").
• Barker wrote the chorus and the bridge. He was still working on a new bridge for the song on the last day of recording One More Time...