Is there anyone else here who rely on the music sheet to learn the piece, memorize it over time, forget about the sheet music then play it from memory?

It's like the piece is already a reflex of my fingers, so I don't need the sheet music anymore.

However, I forget the pieces over time, and I would have to start over with learning the sheet (I forgot how to play Canon in D )

Is there something I'm missing? I mean, I see other players who are able to play while reading the sheet music (with some practice beforehand on the piece). There eyes are able to follow the sheet music while playing, while I can't.

If you need to know, mom taught me the basics, and learned from booklets of playing the piano. Been playing for a year or so.

I think everyone memorises piano pieces, at least, all non-classical players.

I can only play easy songs, like Let it Be and Sympathy for the Devil on piano though.

I've played a little piano, and I had the same experience it mainly comes from not playing the piece very often. And after a while you forget most of it.
I mainly play drums and it's the same thing there really.

It's mainly muscle memory together with developing a good ear for music. Try starting with learning all the intervals by heart if you haven't.

I play a keyboard but I don't use music sheets mostly because I can't read music...but I can play by ear fairly well.

Sightreading (playing a piece while reading it for the first time) is tough, but a really good thing to learn. It helps you learn pieces really quickly, because it develops your ability to quickly translate what you are reading into where you need to move your hands/fingers.

Practice with easy pieces, then work your way up. The hard thing with developing sight reading is getting enough pieces to practice with. You're not practicing sightreading if you keep playing the same piece over and over!

I used to play the piano (long time ago) and I always played while reading. I don't think I've ever memorized an entire piece, except for a few simple pop songs. Couldn't live without sheet music.