I was not a good waitress - too small, tiny hands, klutz-incorporated - but when I worked at the Hilton in NYC, I brought home hundreds of dollars in tips. Unbelievable! But really hard work and the guests were impossible to please.
Similar to playing music for a living!
There was always some clown who would request a totally obscure song from the 19th century, just to mock at me when i had never heard of it.
But I fooled them. Since i play by ear, have a great memory, and parents who sang all the time, I ended up usually knowing the song and was able to present it in an acceptable fashion.
This would usually enrage the perpetrator, as he wanted to triumph over me by his superior knowledge of old music.
And of course, that meant “NO TIP FOR YOU!”