Say you are the THIRD string QB on a really good team. Since you were a little kid, you have played in your back yard, you have thrown footballs through a hanging tire, you dreamed of getting out there and throwing a pass in a game, etc etc etc etc, but it turns out you are the third-best QB on the team. So you stand on the sidelines patiently and wait your turn.
So the superstar starter leads your team out to a 28-0 lead, then the second stringer comes in. He doesn't throw many passes but your team is simply way better than the other guys and you add three more touchdowns and now it's 49-0. So here we are at the end of the third quarter, and you, good hardworking third stringer, finally get to play. And what does the coach tell you?
"Hand the ball off. Fullback off tackle. No option runs, no passes. Kill the clock. If we get inside the 20, just kneel on it."
So you have to intentionally play like ****, you cannot throw a pass, you cannot do any of the stuff you have practiced for years to do, because the other team sucks ass (or more likely, has quit) and we don't want to hurt their feelings.