It seems fear of making mistakes or not performing "perfectly" holds a lot of dancers back from doing their best possible work. This article doesn't specifically discuss dancing, but it might have some useful insights for struggling students...
https://www.freep.com/story/money/business/2019/11/23/josh-linkner-creative-confidence/4271672002/
https://www.freep.com/story/money/business/2019/11/23/josh-linkner-creative-confidence/4271672002/