In an interview, Graham Reid said:

Quincy Jones biggest professional setback
came in 1978, when he served as musical director of The Wiz, a multimillion-dollar flop—but the project solidified a friendship with 20-year-old Michael Jackson… and launched a series of creative collaborations that culminated in Thriller and ‘We Are the World’.

But the strain of living in all those fast lanes, along with the disintegration of his third marriage… drove Jones into a nervous collapse that stirred memories of the near-fatal aneurysm—a hemorrhaging artery in the brain—that had stricken him in 1974 after a similar bout of overwork. This time, he took a month-long ‘spiritual leave of absence’ in Tahiti and returned ‘in control of [his] life for the first time.’

His eclectic album Back on the Block is the harvest of that sabbatical.

In Alex Haley’s interview with Quincy Jones for Playboy, Quincy said:

I just put Big Daddy Kane right on the spot and said, ‘Introduce Miles'. He said, ‘Right, who’s Miles Davis?‘ But they’re only babies – only 21-years-old!’