You mold force into motion. Little girls can do triple jumps just a few inches off the ground because they are quick, while adult skaters can do triple jumps a couple feet off the ground because they are strong. You can often make up for a lack of quickness with strength, or vice versa. In either case, the glue that holds your skills together is sound, fundamental technique. The older you are, the more likely you are to be tense when working on a new or unfamiliar element.
Tension is the body killer.
It causes you to do all sorts of weird things you wouldn't normally do. Often the difference between success and failure is simply learning how to mentally relax. That doesn't mean you relax the rest of your body. Jumping and spinning is all about having tension in your body without being tense. And finally, after all the money, time, bruises, frustrations, lost gloves, bone spurs, lost sleep, neglected work, unfed pets, dirty dishes, and gray hairs don't forget the most important reason for figure skating.