this is a great question. i’ve had my teacher-i think jokingly- say to me “bring this back to me perfect!” i don’t know. i like to move on and learn new things. i have learned a lot since picking up the violin again w/this teacher in feb. but…i am the one that always suggests that he gives me something new. -he never objects to that though. the end result is that i have plenty to work on.-almost too much because he still wants to hear the old stuff really good, then we play all of the new stuff. great question.