Sometimes it can an art can die because it has lost its origional teachings, its not always evolution it can be rediscovery. As i have also said no martial art can claim to be the best as art suit different people in different ways. You can also have fight happen where a black belt in Karate has been a first degree for 10 years and a black belt in another art that has been at rank a year. there are good and bad practitioners in every art, this we accept and have no choice but to accept. I think sometimes we make the same point but in a different way. All martial arts reach a pinnacle of simmularities. A punch is a punch, a knife hand is a knife hand, an elbow is an elbow, but delivery is very different.