Ah man, I felt the same way until I really put in the effort to learn it properly, and it finally clicked. Fighting more than one person is meant to be almost impossible to win. It forces you to choose your fights more carefully when you're outnumbered as you would in reality, or at least use your brain to reduce their numbers or isolate them before taking them on. Or even just get really good at lining them up so you're only fighting one at a time, as you would probably do if ever you fought two people in real life.
I think I've only once won a fight against three. When I see four I just turn away automatically.