My sisters and I booked appointments for haircuts here the day before my first baby shower. When we arrived they told us the hairdresser had not shown up for work and was not answering her phone so they could not take us.
When we had made the booking we triple checked they could take all of us because we had some other appointments to wrap up before the event.
The one hairdresser working was going to be at least another half hour (which was passed our appointment time anyhow) and was visibly angry we were leaving.
I get she probably rents the chair and didn't want to lose business because her colleague was a no show, but we just didn't have the time to wait on her to do us one by one.