There is an enormous benefit to having a really good teacher or coach to help the students who got something subtle a bit wrong way back up the chain. You need someone who doesn’t only deeply understand how to do the task perfectly, but also has a deep understanding of all the different ways the task can be done improperly, and what the underlying misunderstandings or problems are which cause those mistakes, who knows the best way to nudge the learner back on track, and who has endless empathy and good will and enough time to make sure the correction happens.

I recommend Shinichi Suzuki’s lovely little 1969 book about “talent education”, Nurtured by Love, https://amzn.com/0874875846