You don’t, either.
Teaching repertoire is an essential and primary part of my week-to-week rehearsal work However, it’s not the point and I do well to remember that every week.
I teach music. The repertoire is a tool to teach concepts and strategies that my students can learn on the next piece, too.
I teach artistry. The repertoire is a tool to understand the difference between a competent performance and an artistic one.
I teach humanity. The repertoire is a tool to facilitate student thinking about the human experience.