Mobb Deep's Havoc recently revealed that things between G Unit never quite became what they were supposed to be.

Havoc admitted that G Unit didn't really embrace Mobb Deep, especially after their album didn't sell well. In an interview with XXL, Havoc says:

"An album is definitely in the sights...It was a problem for Interscope, where I guess they felt that we didn't sell enough records for them at that time. So they let us go off the roster, & we was like, the stipulations in contracts was real technical so after that I think the G unit contracts just expired. [But] we [won't] stay homeless for long."

Source - HipHop Blog