For me its about anxiety, and that ability to drudge on.
Certain parts of my brain fatigue and completely turn off. After an all-nighter my emotional resilience is off the charts the next day.
I think a little slower, but so much more calmly, and logically.
At my startup my co-founders actually requested I pull all-nighters before pitching VC's because the effect was so profound. Public speaking is so easy when you stop caring and treat everything like an item on a checklist instead of a potential catastrophe.
In my experience, I think the momentum/flow and thrill helps. Also hacking turns into late-night-hacking as I try to dig myself out of hole. So it ends up being productive by trying to finish something before bed.
Two, you know it's painful enough that you'd rather not waste the time doing something stupid and worthless.
Three, it lowers your mental state enough that you'll just drudge on like a robot.