Coaches leaving is a part of the NFL. Coaches leave for other jobs because they are either getting promoted or it’s a better opportunity for another reason. Organizations have to replace assistants all the time. The Colts will be no different soon.
Last season, they had three first-timers at prominent positions; head coach, offensive coordinator, and defensive coordinator. All three did very well. The Colts aren’t worried about losing Frank Reich, but soon they might have to be worried about losing their coordinators.
Nick Sirianni did a good job last season as offensive coordinator. He helped develop offensive players and strategized with Reich to call the proper plays.