"Paul Graham wrote about the maker’s schedule (...) a schedule for those of us who produce stuff. Working on large abstract systems involves fitting the whole thing into your mind – somebody once likened this to constructing a house out of expensive crystal glassand as soon as someone distracts you, it all comes barreling down and shatters into a thousand pieces. (...) This is why programmers are so annoyed when you distract them.
The sleepy brain (...) Why then do we perform our most mentally complex work work when the brain wants to sleep and we do simpler tasks when our brain is at its sharpest and brightest?
Because being tired makes us better coders.
Similar to the ballmer peak, being tired can make us focus better simply because when your brain is tired it has to focus! There isn’t enough left-over brainpower to afford losing concentration.Bright computer screens (...) This one is pretty simple. Keep staring at a bright source of light in the evening and your sleep cycle gets delayed. You forget to be tired until 3am. Then you wake up at 11am and when the evening rolls around you simply aren’t tired because hey, you’ve only been up since 11am! "
More @ Swizec.com