Rock Bottom is a cover band covering the music they grew up with in the '80s. Heavy on AC/DC, they also cover songs by Quiet Riot, Judas Priest, Def Leppard, Metallica, and other great metal acts from that era.
While three of the members of the band were childhood friends, they gradually drifted apart as they entered adulthood. Fast forward 20 years or so, and they somehow managed to reconnect and started jamming together, quickly adding a friend of the drummer's who hung out during their Saturday evening jam sessions. These sessions became more and more regular, and Rock Bottom was reborn. And after what seems to have been an eternity, they have finally found someone to do vocals.
Rock Bottom was the name chosen for a version of their band during the '80s, so when it came time to name the current iteration of the band, it was eventually settled upon after a couple of other choices where found to already be in use.