The deck isn’t always stacked in your favor in performance.
Maybe the acoustics of the hall make it difficult to hear; maybe your section leader double-booked himself and is missing the performance; maybe other members are sick and throwing up just off stage.
Maybe it’s all three of those things. Or any number of others.
No performance is perfect and no performance has to be catastrophic.
It is your responsibility to deliver the best music you can. Sometimes that’s relaxing into the performance you are comfortable giving.
Other times, it’s resolve: intently giving the performance you want to make despite adversity.
It requires strong will and confidence; it requires the hard work of knowing your part so well you can sing it when you are the only one left. It requires trust in the singers around you.
Music is waiting to be made every time a choir begins to perform.
Do not let temporary challenges get in the way.