Today I handed in my exam marks for the module I teach (formal language theory, not that that's relevant to this discussion). Always good to get that task completed. The exam itself was about a week ago. There is scope for debate on whether examinations are more onerous and disagreeable for the examiner, or the examined, and this is the sort of question one considers during the exam itself, while one is invigilating it.
Of course, you usually get to invigilate your own exam, as I did a week ago. The session just involved my own students; there were no other exams being taken at the time, which simplified it a lot. A far cry from the glory days of my invigilation career back at Warwick, when some sessions had about 300 students, taking half-a-dozen different papers between them, all ending at different times. If you had to make an announcement, you needed to repeat it in about 3 different places, although later they installed a PA system.
Examinations, like degree ceremonies, are something of a ritual, and like degree ceremonies, they provide some of us (namely the invigilators) with an excellent opportunity to enter into a pointless and unproductive reverie about the academic process. The instruction is given to begin. The room goes quiet, that is to say, even quiter than it was. As for a degree ceremony, you get the feeling that it is intended to be caught in a time-warp. There should be a battered wooden box on your desk, inked-stained and chalk-dusty, containing miscellaneous things like treasury tags, elastic bands, and anything else that might come in handy. There should be numerous piles of different kinds of answer sheets, dog-eared log table books, and spare scraps of paper. If it's a big session, the senior invigilator will dutifully make handwritten notes on who leaves the room early, and when, and he will direct his underlings to sort out the scripts and escort assorted students when they take toilet breaks. No-one ever wants to be senior invigilator, of course.