I'm pretty sure that's Zen.

Have you ever walked in to your house and saw another man sit on your favourite armchair and play your guitar?
And then, just as you're about to let 'im have it, you stop dead 'cause you realise "Man, he plays it better than me."

It goes a little bit like this: People are just naturally suited to doing things. Maybe you like the idea, but if you can't do it after a while, you never were that person anyway.