In this culture, she is considered lesser than the other soldiers because she is not a man. Mulan has to work somewhat harder than the other soldiers since they have had at least some kind of training in their past, while she hasn't. Even though she knows it will be difficult, she doesn't give up. Instead she keeps going, has endurance, and even comes out to be better than the other soldiers.
In a way, Mulan is similar to Hank, a former college basketball player, and completely different from our society today. Hank was in the middle of a basketball game when he fell and blacked out a couple of seconds. The doctor told him that he had a heart condition. Instead of giving up on basketball, he decided he would fight it and not let it slow him down. In our society, it seems as though whenever any obstacles come our way we give up before even trying to overcome them. Can you imagine how many things could have been improved in this society if we don't give up as much as we do?