I have yet to come across a person in life who has regretted training in Martial Arts. Almost everyone has come across as a humble, well rounded, confident individual.
When asked when they started training, again, almost all of them say they wish they started earlier in life! My oldest son just earned his Black Belt at Point Blank Martial Arts and he started training when he was 5!
He's ridiculously good. Having seen him grow from a boy to a man; from a white belt to a black belt, has been a wonderful experience. I have seen this growth through the eyes of a father and as an instructor. His outlook on life has always been positive and joyful through all his ups and downs.
This is an experience and attitude he carries with him based on years of successful training and participation; interaction with classmates of all ages; helping others when needed and accepting guidance openly.
I have posted this on a couple of my training pages, but in case you missed it, here is a spot on Jimmy Kimmel where Conor McGregor discuss his journey through Marital Arts and the growth kids will take on this journey as well.