From my uninsightful survey. If you were a band, of any genre(the question is not what genre you are), why would the band break up? Creative differences? Lose half the members to drug overdoses? Everyone's boinking everyone else and it turns into a tangled love web? For me, I'd say one of the band members would get depressed and the band would drift apart and everyone would have a short solo career before coming back together twenty or thirty years later.