There is a large portion of music performance that is simply muscle memory, but probably a larger portion is really perceptual. In order to develop better moto

There is a large portion of music performance that is simply muscle memory, but probably a larger portion is really perceptual. In order to develop better motor skills, you need to be guided by the resulting sound compared with an intention, an idea of the sound you want. This implies that the first thing that has to change is perception and imagination. There's a literature on how to practice music. Many of the techniques you'll encounter really have to do with aiding perception (the idea, the sound, awareness of what you are actually doing) and interfering with "muscle memory" so that you can break down and improve execution. Coordination, rhythm, or pitch will not improve until perception does, but perception can certainly be trained and improved! Also -- just try practicing something intensely for 10 minutes, then practice/play something else. Then come back next day after a good sleep. The improvement that happens while you sleep is almost creepy.