LOTUG and Lost Boyz came to mind. After dropping dope debut albums (Here Come the Lords and Legal Drug Money) they followed up with lackluster material (Keepers of the Funk and Love, Peace & Nappiness). Not saying that album number two was wack but it could have been much better IMO. In LOTUG's defense I just don't think their style of rap held up well with the level of lyricism displayed in 94. Who else can you think of that dropped a dud the second time around?