[ZGoten]

Because Vergo's leg is hard, even if he doesn't try, and because Sanji kicks that hard leg hard, even if he doesn't try.

It's like eating soup. If you try really hard and you want to eat it as fast as possible, you are likely going to get your shirt wet, even if you try not to. But if you just casually eat your soup, while being distracted by TV or something, you don't try to avoid getting your shirt wet in the first place, which is why it's not unlikely that it'll happen again. You should eat more soup, man.