“Doing the same thing over and over and expecting a different result is the definition of insanity.”
or
“If you want different results, take different actions.”
I understand the point of these.
But also, when I’m learning to play a new song, I’m doing the same thing over and over with the intention of getting a different result.
Yes, sometimes practice feels like insanity, but sometimes, that’s just what practice is—the same thing over and over with the expectation and hope of, eventually, a different result. (No, practice is not always like this, but it definitely is sometimes.)
Maybe we need to redefine insanity. (Or use the actual definition instead of the kitschy, judgy one.) Or accept that, like everything else, context matters.
I would argue that if you’re practicing correctly, you’re NOT doing the same thing over and over again.
Instead, you’re evaluating yourself and improving something each time, or at the very least you’re committing a bit more of the piece to memory. So each time through the piece will be different, hopefully better.
If you’re not doing any of that when you practice, and you’re just mindlessly blowing through the notes without paying attention or making any effort, then yeah, you’re insane. But that’s doing it wrong.