I think that rappers who drop albums every year over expose themselves and then people get tired of them (looks at DMX albums). Watch when Game and Mike Jones drop their new joints, when some of us are still listening to their first joints.
However some rappers take too long to come out with their next album (looks at his Internal Affairs and Black Star album and begins to ). When this happens, people tend to forget about them and their time passes. (looks at Uptown Saturday Night).
How many years should a rapper wait in between albums?