OUCH!!! You don't believe there are high quality black coaches out there?
If a quota meant taking a not highly qualified person, then I would agree with you.
No, black coaches are not worse than white coaches. And of course there are quality black coaches out there, I wanted the Giants to hire Flores! Plus you know my thoughts on racism, so you know that I didn't mean that in the slightest. Black cricket players are no worse than white players, so why does the quota system ruin South African cricket? I can't give you an answer that's proven 100%, but I can throw a few guesses out.
They end up rushing players who are still too raw, which in turn ruins their confidence when they underperform.
They don't earn the respect of their teammates because everyone knows they were a quota selection.
They don't earn their own self-respect because they know they were a quota selection.
IINM, there were instances of rushing back a player from injury to make a quota, which ended up ruining their career.
I think if racism was removed from NFL hiring, the quality of the NFL would improve because the coaches would be chosen from the best candidates, instead of only the white candidates. I don't think a quota gets you there, and clearly the Rooney rule doesn't get you there either. I can't think of a rule that would accomplish this, that's why I was asking if you could think of something.