You’ve always got a perfect game before you start.
There’s never an out-of-tune chord in the silence before the downbeat.
Every student masters every concept you instruct–until the first day of school.
You will make mistakes. You will have poor tuning, wrong tempos, poor literature choices for your choirs.
But the messiness of doing is preferable to the perfection of not having started. It’s true in all art, including teaching.
Best of luck to teachers going back in the next few weeks (or already returned.) Your perfect game won’t last, but you will make a difference.