As Galileo Galilei said, "we cannot teach people anything. We can only help them discover it within themselves" .
If, indeed, there is nothing that can be taught, there are only things that can be brought out from inside us. That means that every great thing that has ever been done by a human being is just as achievable by any other human being, under the right circumstances.
It means that for any activity that you can think of it doesn't matter how good someone is at it; if you put in the hours, you will one day be just as good. Maybe even better. All you have to do is want it enough.
It means a lot to me when I see this kind of spirit displayed by the guys on the mats, be it in BJJ or CMD. It's so cool to train with guys who both really want to be there, and who have the right attitude.
It's even cooler to be there on nights when people have those lightbulb-going-on moments of enlightenment, and to see everything click for them.
I'll end with a paraphrased quote from the Hagakure:
It is spiritless to think that you cannot achieve what the masters have achieved. The masters were men. You are also a man.