Improvising something altogether new
A classical musician is a re-creative artist.
While there’s much to be said for expertise and technique, you’ll never find or reveal your own voice. At best you’ll be a perfect copy of the original. It’s a neat party trick but not the best - or most fun - way through this life.
A jazz musician is a creative artist. Being a perfect copy of anything is not the aim of the game. It’s improvising something altogether new.
Whatever your art, you want to be a jazz musician.
You want to make it up as you’re going along.
You want to make it all your own.