Stance and movement
Some martial arts teach awkward stances and movements. This may be okay as related to the art part of a martial art since good art is in the eye of the beholder. However, when it comes to the martial part of a martial art, these awkward stances and movements are counterproductive.
If a baby human is left in the forest and raised by wolves, such as in the legend of Romulus and Remus, at some point the baby will stand and begin to walk on two legs. This will occur without the baby ever seeing another human to imitate. The child will walk naturally and make needed stances without any instruction from a martial art “master.” As the child gets older and becomes an adult, he or she may become less physically fit and become lax in making effective stances and movements but the instincts are still there so he or she will still be able to use them if necessary, especially when fatigued. For example, if you turn your head to look over the left shoulder, your left arm naturally extends and right arm relaxes. This is why your car drifts to the right when you check look to the left at a traffic accident as you pass it.
When a martial art instructor tries to teach unnatural stances and movements to students, the students do not perform them instinctively and they must learn how to perform the techniques. Natural stances and movements are easy to perform; the instructor only needs to show students how to perform them better.