This whole "years to master" philosphy is pretty unique to East Asian martial arts--and even then there are exceptions, like muay thai, where a guy can become an excellent fighter in a relatively short amount of time.
When I see a kickboxer or a krav maga guy who's spent a measely year in training hold his own against a karateka who's spent two decades on kata and kibadachi stance or whatever, I feel bad for the karateka. I get it that some people want the "authentic" tradition (or what they think is authentic tradition), but it seems like a waste of time to me.
Comments?
PS
I have some years of experience in Shotokan, so I'm not speaking from a place of ignorance. I feel that life is so much more than "mastering fighting" or becoming the mythical "master martial artist."
Depends on the individual. Style/art is secondary. Some people are just not as naturally athletic and therefore it won't matter how long they train in any art. They would still likely lose to more athletic individual with little to no training.