"No calculation of space and time guarantees victory in this realm of chance, mistakes and disappointments. Uncertainty and the danger of failure accompany every step toward the goal ... In war, everything is uncertain."
...Helmuth vol Moltke, 1869 Instructions, quoted in Hughes, Moltke on the Art of War.
Who are we to argue with the master? However we are not fighting a war, we are playing a game. One of our objectives is that the game be fun; and one of the things that can suck fun out of a game is frustration.
This may seem odd -- after all at some level everything that gives an opponent a chance to win a game frustrates our desire to win it; in this respect the source of uncertainty hardly matters -- uncertainty is just another frustration.
I believe, however, that there are two kinds of uncertainty. The simplest form of uncertainty is simply not to know the situation; in an ideal game, I might have no idea of the enemy is unless I send out reconnaissance. I send out my cavalry -- or not. I am surprised -- or not. The enemy frustrates my intention -- or not. This is perfectly legitimate, and for people who ought to play wargames in the first place quite tolerable. You pulled one over on me, good for you.
In a typical wargame, on the other hand, I know exactly where my enemy is and exactly where my units are. I know where their commander is, and I know there is exactly an 86% chance that they will follow him to a successful attack. I know that there is one chance in 36 that they will do something utterly ridiculous, and in fact on 1/6th of those occasions they will simply march off the table. In fact, I know far too much about what may or may not be about to occur. All that I don't know is what the dice will decide. And when I roll 12 followed by one, I am frustrated; I am not uncertain or apprehensive (which are reasonable emotions to feel in a game with an opponent) -- I am just plain annoyed. Of course I should not have started my attack knowing how it would come out. But this sort of thing makes the dice the main adversary.
Now there is friction in war, grit in the machine, time and chance happen to all. When Steinmetz took over control of VIII corps and drove it to fruitless slaughter at Gravelotte, von Moltke was profoundly frustrated. A very pleasant exercise in frustration can be enjoyed by playing a multi-player game. People are intensely frustrating - but this is a proper form of frustration. Rolling a bungle with the VIII corps commander followed by an uncontrolled advance models the effect. But it does not feel right; it is those damn dice, it is my rolling, it is Fortuna Imperitix Mundi.
Humans personify bad luck. Good gamers work not to, but no one is immune to it. In this design I want to minimize the extent to which I resort to random frustration to model imperfect knowledge and control by the players.