How did ineffective martial arts survive so long?

By "ineffective martial arts", I mean the ones that aren't stress tested and usually don't stand well in a MMA environment. This includes arts such as Wing Chun and Aikido.

I can see how people love the idea of feeling secure over putting in the actual time in sparring and getting hurt, so I can completely see why most people subscribe to non-stress tested martial art classes and self-defense classes. However, I'd assume over the hundreds of years where these martial arts gained popularity, why weren't there enough people questioning the authenticity of the art?