Well, he thought he had contributed the most to the band, being a founding member an' all, and thus he also thought he deserved the band's name - out of pure conceit - because he thought he was the most skilled in the band.
Luckily, he only got rights to the name "The Wall", and after that dispute he launched his solo career! ;D
[I'm glad as hell he didn't get the name.]
[Oh yeah, Pink Floyd's my favorite band.]
@markj, I'm just going to have to stop you there. "The Final Cut", "A Momentary Lapse of Reason" and "The Division Bell" were spectacular albums, even though Waters contributed absolutely nothing to either of them. Most definitely not SOFT rock, but PROGRESSIVE rock. Big difference.