I don't think most guys are ugly, and even if they are, that's not the reason they aren't getting laid. Getting women is a snowball effect. You need to get a girlfriend early. Once that happens, other girls will like you because the first girl liked you, and they will let you smash. After a while, you become known as the guy that gets girls, and that will help you continue to get girls.
If you don't get a girlfriend early because you got cockblocked, or developed a reputation for being a clown, you won't get the first girl, which means you won't get the other girls. Women are going to give you a lot of resistance over the course of your life, because you're known as the guy that can't get girls.
If you find that you have a bad reputation, it's time to move and become the new guy, because you're screwed.