It’s my theory that the back ups are usually the hard working gym rats that love the game and who aren’t typically the most talented. Those are the types that become coaches.
The most talented players tend to be less coachable because it comes so easy for them and held up on a pedestal that hard work wasn’t a top priority…. Don’t get me wrong, most talented player AND hard workers are your Hall of Famers but still not likely to be a coach.
That’s my basic theory on why the back ups make better coaches.