It's one of those interesting confluences of faith and practice.

One reason besides god-given (genetic?) talent, that some learn faster is that they stumble into (are directed to) the proper things to practice.

You can spend one hell of a lot of time praticing the right thing the wrong way.

In order to even come to the point of "muscle memory" your muscles must have at some point in the practice achieved the proper result that you wish to duplicate...if not all the practice is at best, retarded.

You can play some pretty terrific music "retarded" though.
Where faith comes in is that, at some point you have to trust in some way of doing it....and practice that...and hope it's a "right enough" way to achieve the result you want.