I've sat through a festival performance from a trio that were usually quite good, but the singer was monumentally pissed, and consequently couldn't carry a tune in a bucket....

It was obvious to all but her that it was awful, the band tried to play a bit more strongly, to encourage her into the right key, but it didn't work. Had I been them I would have closed the set, got the hell off stage, returned the fee, got the singer sobered up and apologised. They were never booked there again despite previously being regulars and have since split up (although that wasn't anything to do with this particular event), but this left a bad taste in the mouth for all concerned.   It was a shame because she normally isn't that bad... but that one performance queered a lot of pitches for her.

Everyone has bad days. If every day is a bad day, then maybe they should be encouraged to find another outlet.

LTS