What successful college coach has failed in the NBA and then tried again and was successful? Maybe there are a few isolated examples, but you don't see Eric Musselman, Larry Krystkowiak, Leonard Hamilton, Lon Kruger, or obviously John Calipari looking to return to the NBA. Am I missing anyone?
Conversely, I doubt we'll see Avery Johnson try to coach at another college program after his mediocrity at Alabama. Of course, Billy Donovan and Brad Stevens have been able to succeed at both levels, so that's irrelevant.
I don't watch the NBA, but my understanding is that while the styles of play between the two levels are converging, what it takes to have the right roster to succeed is so different between the two levels.