What does day/night length do? Am I suppposed to go out at night?

[roustingRosy]

After playing a first round, I started a new game to explore a bit more of the map and get some missing achievements. I set the day length to long and night length to short before starting, but the night is still 14 hours and the day is 10 hours, just like when both is set to medium. Does this actually do anything?
And am I supposed to stay inside/sleep during the day and sexplore at night? Because in that case, I've been playing wrong the whole time lol