Been there and had to do that, although that was largely down to me being the band songwriter and the singer not always liking what I was writing for him. It was the best thing I've done (deciding to handle lead vocals that is), with the added bonus of reducing the size of the band and thus making it easier to control What was that about rock guitarists again ....... ?Me.
Our lead singer just quit the band because he wanted to go "Total Dance Music" and I wouldn't. He now wants to be a dj and "keep up with the newest dance tunes."
Uggh. Guess I'll be singing.