Ice cream too cold. Not freezer burnt, not too hard or had thawed/melted and refroze, just it was too cold.
After explaining to them it was not going to be a Mr Whippy in a cone but a quenelle.
Too fucking cold and it hurt her teeth.
Either that or someone who ordered steak and changed to a salmon dish after it had gone out because they saw cows outside being herded up the road, but they were big tippers laughed at themselves and very apologetic so no hard feelings there.
Source: old.reddit.com