Before I got into my current job (which I actually like) I got to experience the misery of working at a call center where customers call to book taxis. Every shift was 12 hours long and you were not allowed to take breaks. You had to sit at your desk for 12 hours and only get up to get some water or go to the bathroom.
No words can explain what it was like except pure, utter, grueling, Hell. There were regulars who called who were clinically insane. One lady used to have a driver pick up food for her and deliver it to her door, and she would always call and claim that something was missing, have a literal 5 minute shouting monologue, then say that she just found the missing item in her bag.
Another lady would call (fuck you Michelle) and with the snootiest voice would literally start to cry if the driver did not pick her up from exactly in front of her door.
Another lady would call and instruct us not to send her any black drivers (the drivers were all outsourced from a couple of countries so they were basically all black).
I would throw up with anxiety every morning before my shift.
I quit one morning when I came in at 8.03am the day after a 12 hour shift which had ended the previous night at 9pm. I was supposed to start at 8am and the t team leader yelled at me about it. I told her I’m done and handed my headset to hr, who proceeded to call me 3 times telling me to come back to work when I have calmed down because they are too short staffed.