For the most part, I try to present plot arcs that have a beginning and an end. This makes for satisfactory story telling for the participants to feel that something is beginning and something is ending. In between, the players have a lot of options.
The best outcomes are those that seem to come from the players’ free will, even if they know damn well you’ve got a module in front of you. These days I find quite often that the players pick up on the plot hooks and run them down, though it worked fairly well back when I’d get players who would lead the party on wild tangents. If Mohamed will not come to the mountain, the mountain must come to Mohamed. This is in fact precisely the GMing style we learn from The Bible. Obsreve:
God has a story he wants to tell, and it begins with Adam taking a bite of the forbidden fruit. So he tells Adam, “There’s the forbidden fruit, of which you may not eat.” Then God hides in the bushes and waits. Adam doesn’t take the bait. God can’t just say, “Adam, you eat of the forbidden fruit. Now come the consequences.” Adam would say, “My character would never do that!” Adam must choose of his own free will.
So, God brings in a new PC, Eve. There you go, kids, have fun, don’t touch the shiny, succulent forbidden fruit. Well, they don’t. Damn it!
So, God puts a serpent in the garden. Bingo! The plot starts getting traction.
I’m not saying that God is always a good GM. Moses keeps acing his Diplomacy and Intimidate checks, but God doesn’t want the Pharaoh to let his people go. He hasn’t mapped out the desert yet, or something. So he keeps “hardening the Pharaoh’s heart” against Moses. So, all these points Moses put in his social skills are just wasted, right? Because Moses can’t possibly affect the outcome, and Moses’ player is probably feeling more than a little screwed by bad GMing.
Infinite free will, however, is not really the point either. There is always an obstacle, and sometimes that obstacle is a train that you must ride.
Here is an example of a perfect story, as related to me in a fiction workshop: A man is walking along and sees a blind man across the street. A dog is pissing on the blind man, and the blind man is trying to feed the dog a sandwhich. So, the man crosses the street and says, “You know, that dog is pissing on your leg.” And the blind man says, “I know, and as soon as I find his face with this sandwhich I’m going to kick his ass.”
The story is perfect because everything that happens happens because everybody in it wants something. The dog wants to relieve himself. The blind man wants to kick the dog’s ass. The guy walking along wants to know what the hell is going on. In a roleplaying game, the party’s desires generally start out pretty simple. They’re in a tavern because they want to find a party and go have adventures, possibly picking up gold in the process. Ideally, their motives eventually get more complicated.
The GM’s job is not simple wish fulfillment. There will be times of respite and reflection, and times of reward, but no one is going to enjoy playing a PC who has got everything he wants and has nothing left for which to strive. The GM must keep throwing problems between the PC and his goals. Usually these problems are going to be planned ahead of time, but often and especially if you’re determined to go freewheeling as much as possible they must be constructed on the fly. But the fact that the GM is doing the PC no good by simply giving him what he wants is very handy for generating things for the PC to do. The PC wants X and you say to yourself, “What will I make the PC suffer before I let him have X? Or X/2…?” When in doubt as to what to do next, problematize.