When my son was in 8th grade the new AD at the high school hired a new baseball coach. The previous coach (17 losing seasons in 20 years) was owned by the parents. The new coach would have nothing to do with parents. He went too far the other way. But it was easy to understand why. He spent the next two years weeding out cancers and kids who didn't work out in the offseason. Of course, this coach was accused of rampant favoritism. The parents tried to get him fired. My favorite line from the new coach was, "Sure, it's ok to go on vacation and miss two games. Turn in your uniform before you leave and miss all of them." The dad of the shortstop went nuts when my son (an 8th grader) was brought into several varsity practices. He was telling the shortstop his job isn't a lock next year.
My son played three years of varsity ball. I saw the coach get opening day rosters and lineups wrong all three years. But he had it corrected by game five. I probably knew more about the players than the coach from summer ball and more exposure seeing them in games.
One kid was in the starting lineup for four games his soph and junior year. I had this kid pegged as a player the coach overrated. He was a great practice player. After going O-fer with nine or ten Ks in four games each year he would lose his position. He didn't try out senior year. The dad said it was because the coach plays favorites.