Makes sense! This I can understand. Analogously, at the end of a software project you tend to have to take care of all of the little things - re-run all of the tests, figure out the packaging script, fill out paperwork, make sure the website is ready, etc. This sort of stuff can be done on relatively little sleep with few breaks. I was imagining the interns putting together models and doing lots of calculations in that 80th hour - seems like sooner or later this would be disastrous.

Thanks for answering the question :)