Concluding my remarks from this post and this post, the reader may remember that I ended by saying that a DM ought to combine both preparation ahead of time with on-the-spot decision-making, which I have described as using a heuristic. The word is unfamiliar, so once again I'll quickly say that a heuristic is a decision that is made from the hip, with minimal evaluation of the facts, heavily weighted by the individual's present mind set, biases and experience.
We've talked about how a heuristic can be a negative thing, based on weak or cliched information. We've also talked about how a heuristic can enable a DM's rapid response to game play that is flagging and requiring momentum. To that, I'll add that all DMs must be ready to think fast on their feet, given the amount of information that surrounds game play and the potentially pattern-breaking behaviour of innovative players. A DM can easily feel overwhelmed by all this and unable to make a patient, well-grounded conclusion. Heuristic decision-making is, therefore, a prerequisite of DMing.
But I stress that it is also a prerequisite of playing an RPG. Virtually every decision a player makes during the course of the game is made heuristically, without any warning as to what to expect and without the time to piece together a detailed assessment of the problem at hand. Even in the case where the players have time to plan an assault on a given lair or descend into a dungeon, where they can equip themselves and gear up mentally for the offensive, they still don't know what they're going to encounter before they do. The DM can take steps to select what can be prepared and what can be left to a heuristic, but the players don't have that luxury.
This gives the DM a tremendous advantage over the players. It also speaks to the DM's mindset where game-play is concerned. Arguably, DMs are the sort of people who are made uncomfortable by heuristic decision-making, who prefer the option of planning things out ahead of time. They are the sort of people who, when making a heuristic decision with unforseen and unpleasant ramifications, want the option of reworking the setting and experience in order to protect themselves. Players are necessarily subject to the consequences for their actions, being limited in the amount of power they have in a campaign. On the whole, players are stronger, more ready for the chain reaction of play, having less issue with the potential failure that can result from rapid-fire decision-making.
Yes, I am saying that DMs have the weaker personality. Or, if the reader prefers, the more defensive personality. Very rarely does a DM have to accept the mistake they've make and suck up the consequences. Like an eel, the DM can almost always shift the liability onto the players ~ who, often without complaint (or unaware), accept the burden and keep on going. I don't say that they accept the burden quietly ~ not remotely! ~ but they do keep moving forward.
So this brings us back to the decision to play D&D, or more specifically the reason why some choose to DM. The non-specific answer, "the game challenges me," is made more clear in that the game's challenge is in requiring a string of heuristic, off-the-cuff answers that promotes a feeling of stress and risk, resulting in an increased chemical rush of adrenaline and dopamine, particularly when the risk pays off and the character survives. Fundamentally, we're all just natural drug addicts.
The DM goes one step further in this process by extending the "game play" to quiet afternoons and evenings spent preparing the game in advance, boosting expectation and allowing the DM to "edge" for a longer period of expectation before the game actually occurs, knowing consciously or subconsciously that whatever happens, the system/structure/campaign can be adjusted to ensure the DM's deficiencies are minimized.
Take the time to write down four or five game-changing decisions that have resulted from the reader's involvement in recent games, then take the time to consider the motivation behind each of those decisions. In most cases, if the reader is honest, there won't be one. There will be a strong inclination to invent a motivation, to rationalize the moment the decision was made in some context that will offer logic or reason, but more probably the decision was make heuristically, without any plan or solid thought process in place. Resist the inclination to rationalize. Accept that hundreds of hours of game play have created an acceptable experience-based patterned response to in-game events that allows the reader, when participating, to simply "go with the flow" in the same detached way that we would watch a movie or participate in a football game.
Embrace this. Where a snap decision seems to have caused a misstep or resulted in the downfall of a character or the party, trust that the lesson has been learned and that your judgement next time will be improved. We know that when we have the time to examine something ahead of time, it may still go wrong. On the whole, we're doing fairly well to stay alive as long as we have in a situation where we're making split-second guesses against a die that may not support our chances for success.
Regarding DMs who may not be aware that they are unconsciously making decisions that re-route the campaign in order to protect themselves, I can only suggest that we should all stop doing this. It is very easy to do, it is very tempting to do; it is also loathsome and indefensible. Be aware, however, that we are doing this. We have the power to do it and corruption has a nature of slipping past undetected. So often, it is done without a moment's thought, utterly as a heuristic. It is only by going back and evaluating our performance, night after night, that we can recognize patterns where our behaviour comes short of legitimacy.