Jerk move: Having a side project that takes up more time than your main gig.
Case in point: Peter Hook of New Order. Frontman Bernard Sumner accused bass player Peter Hook of being so busy being a celebrity DJ that the band couldn’t make a new album. Hook responded by saying DJing was a far more satisfying activity because there was no-one to have an argument with. The bassist has now left the band and Sumner told the press they were far happier without him.
The right way: Josh Homme. Dude has a approximately 73,491 side projects apart from his main gig, Queens Of The Stone Age, and they still managed to release an album that just might be their best yet.