I think I have found a way for someone to keep attacking until they miss. You need two levels of siegebreaker fighter, eleven levels of fell rider cavalier, and the shield slam feat. Shield slam gives a free bull rush on hits with a shield, siegebreaker gives a free overrun if you succeed with a bull rush, and fell rider can make a free attack if overrun succeeds. Does this work?
Sorry if this has been asked before I am bad at using search.