Because if anyone in here was qualified to be an NFL coach, they would have the drive, determination, and commitment to become an NFL coach and would never be posting on this forum board. You are not given anything in this world, you have to earn it.
What if life circumstances had precluded such an opportunity? What if they just weren't interested?
I've often said that the best QB to ever play never played; his interests were elsewhere besides football.
Example: My nephew is an incredibly gifted natural athlete- who has no interest at all in sports. He's geared towards computers and the arts.
There seems to be this idea that the guys in the NFL coaching and front office positions are the only ones in the world who can do it, as if they were some God like beings with special powers and were privy to special secret words that us mere mortals couldn't begin to understand. It's if that's your goal and focus, and if you have the opportunity, then you get the shot.
I don't know where "You are not given anything in this world, you have to earn it " comes in, but believe me, there isn't anyone on this planet who knows or understands that better than me.