I can easily see a girl coming from dance/ballet, or gymnastics, or skating, or cheer being a natural in most other youth sports. The athletic ability necessary is mind blowing. The willingness to make the personal commitment to working toward perfection is a norm. Girls seem to gravitate to what they are truly passionate about. It'd be very rare to hear a complaint from a coach that a girl involved in these sports wasn't all in. We see it all the time in the most traditional boys' sports.
The coaches are tough on the girls. Not mean, but really push in an encouraging way because they know the girls are so devoted. High expectations are common. A lot of us would cry foul about a youth baseball program that demanded so much from a boy. We're talking about taking on a lifestyle. Not to mention girls from these type of backgrounds are used to being center stage. Confidence runs really high here. I don't think it's an "I'm out to prove something" thing.
It's just a matter of physically staying on par with the boys which eventually will come to an end. That and the sports I mentioned require a tremendous amount of sacrifice. School, a little time with friends, and basically everything else devoted to perfection. Gets increasingly more difficult to squeeze in another interest requiring them to be present at specified times.
There are two kinds of losers.....Those that don't do what they are told, and those that do only what they are told.