Players have X number of games they can play in a year. If they play in a JV game, it's X-1.

As said, redshirt players can't play as it would burn the redshirt.

So, remove the players you want to keep for real games, ones you don't want injured, and redshirts, you only have a group of players for which the JV game wasn't worth the coaches time/effort to plan for.