1. They didnt get the respect from hip-hop circles. Speech wasnt much of an emcee. They appealed more to the r&b crowd. Along with PM Dawn, they basically created this lane for others to reap the benefits later on.
2. But they still sold a ton of records. The 2nd album had no hits tho, and they weren't signed to a strong label, nor did they gave strong industry backing behind them. Back then, it was easy for alot of artists to dissappear as soon as they started to slip.
They were huge in 92-93 tho. Outkast in the 2000s basically had the run that they should've had. Hell, they're the reason outkast got signed to laface.