For the shortest time to proficiency, Target Focus Training DVDs and seminars can't be matched. For training seminars, Rory Miller's Chiron Training is top quality. After that, it's based upon the individual owners of individual martial arts.
Proficiency is measured as in having at least one technique that you can rely on to save your life. Problem is when the problem can't be solved by that single tool or technique. Martial arts is thus the training to collect techniques, in order to grow the toolbox so that more situations can be solved in more optimal ways.
It's hard to think of an 8 year old, except in exceptional circumstances, as being proficiency in one technique. So the other answer is that the standards for black belt is very low depending on location. When originally the standard for black belt was 1000 hours, while people seem to think black belt means mastery, 10,000 hours.
People can get quite a bit of money if they train for a few hours each year, get a black belt as a certificate of "mastery" for their kids. In reality, that's not so, but few have to test their tools in reality.
There is no universal "best" system to learn; it's all up to you. As I inferred that you are interested in studying a system which is more in depth than giving a black belt to an 8 year old, try tai chi. First learn how to master your self, then other things become more obvious. It will take a few years.
Two schools of thought do a bunch of combat sports and learn how to defend yourself in bare handed combat under diffrent rule sets then test your self in nhb. Combat sambo ,sport sambo and fedor are the best example of this. Then do some sort of self defence crap after. Or you learn real self defence break a few bones and dedicate seven years of your life to learning how to kill then you go kill to hone your skills.
krav maga
I'm a teenager and wanted to start , so I know that if I got into a situation that I couldn't bounce from, ( can't run) I would fight. Like getting mugged , I want to know I have a chance .
Also why do those karate schools give ppl their belts so fast. Like 8 year olds are black belts. I think it's stupid so can i get other schools of martial arts for self defense and conditioning
