Wargames basically want to simulate a real world with all its features, so we don’t need to jump to another dimension or time (and gather troops, supply them, kill a lot of living creatures, risking the life of a bunch of other ones, including ours) to test our tactical and strategical skills (and sometimes, maybe have a little fun). Of course this simulation is not perfect, but some very obvious, real world features are missing in a lot (I wouldn’t risk to say the most, however I think it would be true) of rulesets. Are in these other worlds or times no day and night? No seasons? No weather?