Buffers: the difference between a calendar and chaos
An appointment rarely takes exactly as long as the calendar says. Preparing, clearing up, catching your breath — leave that out and you are running late by the third booking.
Terminy knows three kinds of buffer: before a service, after a service, and the lead time that stops someone booking a slot ten minutes from now while you are still at the basin.
The result is quiet but noticeable: the calendar only offers what you can actually manage.