I mean the only explanation I can come up with is if you're sleep deprived you're assuming that there's a reason for it that's good and therefore you want that of course not with anything the fact the higher cortisol will then I think that's probably the best sort of piece of teleology for that yeah if you're like a basic mammal which means either you are emphatically diurnal or emphatically nocturnal and if instead you're wide awake eight hours into what should be the twelve oh this does not happen by chance the odds are you have something stressful going on I think that's the logic of it