Musicians: Have you ever played a show that you thought went absolutely terribly, and someone comes up to you afterwards and says:
“Dude! You guys were so great- it totally made my night! Thanks!”
Music is very subjective! While you are on stage worried because you missed a few notes or played the wrong scale, most audience members may just be noticing the overall energy of the group, or maybe focusing on how handsome the guitar player is.
So how can you judge if a show was ‘good’ or ‘bad’? My advice is: Don’t. Just be happy you are playing music and that people are coming out to listen. Hopefully you prepared as well as you could, and tried your hardest, so no sense wasting time feeling miserable that you flubbed that B-flat-super-locrian scale. After all, you will have many opportunities at future gigs to attempt to play a technically perfect performance. And a self-loathing musician is not that fun to be around!
Even if I think I played terribly, I’m just happy that the music I played brightened someone’s day.