Let's give an example, for example, if you are a boy, if you are in an engineering college. The ratio of male to female in the whole school is 9: 1, so the competition between boys in the same school will be quite fierce, because in theory, nine boys grab a female resource.

Of course, this is only an influencing factor, because if this boy is good enough to be liked by girls, then he will never lose his girlfriend because of the lack of girls' resources, at most, the number of samples selected will be reduced.

On the other hand, if a boy is sloppy enough, looks blind, has no talent and won't fool girls, then even if he is the only boy in school, the probability that he has a girlfriend is slim.