Agree we are all different and if it is not broken then why try and fix it. There is often a case though for preventing injuries occuring or trying to optimise performance.

Asymmetries are very common.

Do you have problems with your shoulder? / Have you had paticular problems with it in the past?

What sports do you participate in?

Treated a lot of patients who are not symmetrical...due to sports they did....tennis, pole vaulting, boxing...few sports are symmetrical and as previous post noted very few people are symmetrical.