My fingers not going where they're supposed to go

[dontcheeseme]

I'm practicing this simple Grade 4 piece (which is challenging enough for me yet not too hard). And whenever I've almost gotten it down cold, I find that my fingers sometimes miss the keys (they hit the ones adjacent to the target keys instead). No matter how much I practice, they always go to their adjacent keys, even though I have the piece memorized. Does this issue iron itself out as you get better, should I work on the piece until it is 100% perfectly played no mishitting at all, or shall I leave it 85-90% perfect and move on to the next piece, as my aim is for long-term improvement over a period of countless years. Do I slow down the practice tempo to maybe half of the piece's normal speed? Leave the piece be, maybe and let the subconscious work solve the issue, or will this result in bad habits if I just leave the piece be? Do I just have bad hand-eye coordination that will resolve itself eventually?

[ranjit]

And whenever I've almost gotten it down cold, I find that my fingers sometimes miss the keys (they hit the ones adjacent to the target keys instead).

Hitting neighbor notes is very common and happens even with professionals, especially if it's just a few times during the course of a piece.

Does this issue iron itself out as you get better...

Absolutely.

should I work on the piece until it is 100% perfectly played no mishitting at all, or shall I leave it 85-90% perfect and move on to the next piece, as my aim is for long-term improvement over a period of countless years.

That will depend on how much time you're spending on this piece and how it detracts from learning newer repertoire. If it's something you can get fixed in a couple weeks, I think it's valuable to do so. But obsessing over getting a piece completely perfect over a longer period like a few months, unless it's for an audition or something, seems like a waste of time to me, because you will also learn a lot from playing other pieces as well and broadening your general knowledge base.

And no one ever reaches 100% of what they think is possible, there is always something to improve upon. So, trying to polish up something to perfection may well be an exercise in futility. Instead what you need to try and do is learn most pieces to an acceptable standard, and keeping working on different aspects of pianism(technique, timing and rubato, phrasing, dynamics, overarching structure, etc.) and keep learning from the experience. Imo in the initial stages at least, what will determine your progress the most is what you gain from learning each piece, not trying to excessively fine-tune each one.

It also seems like you think of a piece as being played to "100%" if you get all the notes right. That's not really true. I'd argue that most of the music comes from the subtlest expressive nuances which you can generate on the piano, which are usually not even notated. The notes are just a representation of the actual music, and so playing the notes correctly doesn't equate with playing the piece well. So even after you hypothetically get all the notes correct, there is a mountain ahead of you. Ideally, you would be working on both aspects simultaneously (note accuracy and musical expression).

Do I slow down the practice tempo to maybe half of the piece's normal speed?

You should be practicing at various tempos. Slow practice will help with note accuracy and the mishitting of notes. There is no "practice tempo" you stick to all the time. You need to experiment. For example, you could play it at half the speed for 50% of the time, play it in various rhythms for 25% of the time, and play it at full speed for 25% of the time. Or, you could take one or two measures and really drill them. Slow practice is very important while committing a piece to memory imo, you want to try and get as much as you can correct initially. If you keep playing something wrong for a period of several years, it can get nearly impossible to eradicate. While practicing technique and performance, I think it is important to play both at slower tempos and slightly faster tempos (occasionally, that is). For example, slower tempos tend to consolidate memory, and faster ones tend to bring out deficiencies in technique or smoothness better.

Leave the piece be, maybe and let the subconscious work solve the issue, or will this result in bad habits if I just leave the piece be?

I don't think leaving the piece be will result in bad habits. It's often a good idea to come back to a piece later, and I don't see any harm in doing so. In fact, you will keep coming back to your repertoire pieces all the time to incorporate new insights into your playing.

Do I just have bad hand-eye coordination that will resolve itself eventually?

You know, I don't really think piano playing involves that much hand-eye coordination at a high level. It's been my experience that it's all in the hand and the brain. Hand-eye coordination might be useful while repositioning your hands or during large jumps, but otherwise, your hands need to get a feel for the distances between the keys, and move of their own accord without much conscious effort. It's not like a video game where your eyes actually need to be involved. Basically, it's proprioception, not hand-eye coordination, which really needs to be developed in order to play the piano.