Typical HS Coach Profile - Played the game professionally or in college and did not reach the Majors. When playing days were over he finds his way back to his hometown or perhaps his wife's hometown and starts working. Wants to stay in the game and ends up at the local School coaching.
He is competitive and wants to win. He may even have a chip on his shoulder with something to prove. None of this means he is sitting guys that can clearly help the team win games.
The grey area at a lot of places is not in the best 4 or 5 or the bottom 4 or 5 but the half dozen in the middle. In other words the kids that will hit 7-8 or be the 3rd or 4th pitcher.
There will be some philosophical bents, experienced (Sr. vs So. kind of thing), size, speed or attitude factors. But in the end most of these decisions typically leave a team in the same place. How many light hitting outfielders are interchangeable? Most of them are.
If the team is on its way to 17-8 with the coaches lineup, your lineup wins 16 to 18 games too if that is the decision point. Every once in a while a coach makes a bad decision on these kind of things and misses the diamond in the rough or the gamer that might turn that 17-8 to 21-4 or something. I am of the opinion it does not happen often.
On the other hand if you are one of these players and you have an approach, mouth or attitude that rubs the coach the wrong way and he wins 17 games with or without you then you should never be surprised if he does it without you.
I have told my sons that you win 95% of time in life simply by showing up on time with a good attitude. The other 5% is defeated with talent. Whoever has it wins - at everything.