"Firing a college offensive coordinator often only leads to a noticeable improvement in a team's overall performance in a relatively small percentage of cases; while a "bounce" can sometimes occur after a change, it's not guaranteed and is often dependent on the underlying issues with the offense, the quality of the replacement coordinator, and the overall team dynamics, making it a risky strategy with no guaranteed success. "
You have to be darned sure about firing an oc. Ask Utah, it hasn't helped them to fire OCs every other year.