If the late Bill Walsh had the chance, he probably would tell John Harbaugh that he stayed eight seasons too long with the Ravens and not to coach the Giants beyond 2035.
Walsh, the three-time Super Bowl-winning 49ers coach, had a hard-and-fast rule that he shared with Dick Vermeil, Bill Polian and countless others: Do not coach in one place longer than 10 years, because the players tire of your message.
The Giants jumped at the chance to hire Harbaugh because they saw a Super Bowl champion with the 14th most regular-season victories in NFL history (180) and a culture-builder. Not the loser of seven of his past 11 playoff games, overseer of a roster that underachieved (8-9) this past season and leader who stopped getting through to MVP Lamar Jackson.
So, how do you know if a longtime successful coach is just done in one place? Or if he is done for good?