How to Get “Good”
I get a lot of new students asking me how long it takes to get “good.”
Assuming “good” means being able to play something comparable to a popular piece by Chopin, my answer is, “It depends on how much you practice well.” So, in a way, you choose how long it takes to play well (within reason).
This depends on three things: (1) your inclination and desire to practice; (2) knowing how to practice effectively; and, (3) the amount you actually practice effectively.