Sometimes, a villain's biggest problem is that his forces are diminished to the point where they can't stand up to the hero. Sometimes this is simply because The Hero is such a badass that their tactics and training don't help the mooks one iota. Other times, the minions are idiots who can't hit the broad side of a barn but end up being good targets themselves. "If you keep disposing of your men, Sir, you won't have any left."