THEORY: Jon Bon Jovi

After New Jersey in 1988, Bon Jovi deviated from the glam metal sound that had made them popular. 1992's Keep the Faith was nearly devoid of the type of song that brought them fame.
Some songs on Keep the Faith, such as "Blame it on the Love of Rock and Roll" and "I'll Sleep When I'm Dead" sound like classic Bon Jovi tunes. That's because Jon Bon Jovi was alive for them. The title Keep the Faith must have been brought about by a tragic event, like, say, the death of the most prominent member of the band. There's even a song called "Starting All Over Again". The theme of loss and regret continues into 1995's These Days, with songs like "Lie to Me", "It's Hard Letting You Go", "My Guitar Lies Bleeding in My Arms" and "Something for the Pain". Continuing is also a theme, with "If That's What it Takes" and "Something to Believe In".
Jon Bon Jovi 2.0 settled into his role in 2000's Crush, with "It's My Life". However, during 9/11, JBJ2 was killed, prompting 2002's Bounce. I can't explain it better than Wikipedia can.
As we all know, JBJ3 died in 2009, in a fatal car crash. 2010's The Circle was made from his final recordings. JBJ4 is currently touring with the band.

it's like they're singing hamsters