On the other hand you have something [Paul Graham] calls 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 glass and 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.
Because of this huge mental investment, we simply can’t start working until we can expect a couple of hours without being distracted. It’s just not worth constructing the whole model in your head and then having it torn down half an hour later.
In fact, talking to a lot of founders you’ll find out they feel like they simply can’t get any work done during the day. The constant barrage of interruptions, important stuff ™ to tend to and emails to answer simply don’t allow it. So they get most of their “work work” done during the night when everyone else is sleeping.