It's very busy all the time. Very often quadruple sat and tables stay for usually an hour at a time. If you aren't in a good section, you might not make too much in tips, but they move you to the better sections the better you are. There are 250~ ish items on the menu and you're expected to remember all of it, including the things not listed on the menu. It can be a lot, but the large number of people working together helps make it a bit easier for yourself and others.
Discounted food, easily promoted if you're a hard worker, professional cleaning crew, little sidewalk
Very busy or very dead, no free food unless you work a double