Usually means when
a reputed band of the alt. rock persuasion who sells themselves out to make a mainstream, top 40 hit song or album.
The definition was derived
from the popstar
Avril Lavigne's own hypocrisy and stupidity on her own career
she first debuted she was touted as the Anti-pop Britney, singer. But as her career
progressed she changed
her image and persona into
something which contradicted her own thoughts and actions.