Basically because rap was awesome.
Speaking to New York Times Magazine, Quincy Jones addressed being passed over – and not informed – by Michael Jackson following his work on the legendary Bad.
He didn’t, no. It’s O.K., man. It’s not like I’m gonna roll over and die. He told his manager that I was losing it, that I didn’t understand the business because I didn’t understand in 1987 that rap was dead. Rap wasn’t dead. Rap hadn’t even started yet.