"The GM is the author of the story and the players direct the actions of the protagonists."
"So, who makes the decisions in a role-playing session - positing that this role-playing session, when all is said and done, is a Story of this kind? Someone has to do it; they don't happen by themselves.
1. The GM does it. The players have "choices," such as being allowed to squabble in a picturesque fashion between important scenes, or being able to choose what weapons to outfit themselves with. But when it comes to the story choices, the GM's all set. Maybe the GM made those decisions before play; maybe he improvises them as the group goes. Doesn't matter. If he's unsubtle, it's "shut up and get in the death-trap" time. If he's subtle, then whatever the players do, the GM will transmogrify it into a decision of story significance.
2. The players do it. They really direct the actions of the protagonists, and, unsurprisingly, may play a big role in engineering the situations which cause the characters conflict in the first place. The GM in such a situation plays a facilitative role, perhaps an aggressive one or perhaps a mild one, because he cannot decide when the conflict is the conflict, far less how the character will address it."
"Meanwhile, the players are unaware that their actions have no impact on anything. They sometimes succeed and sometimes fail, and it all seems to fit together. The amount of power the referee has to control events through the credibility given to him enables him to completely hide the fact that nothing the players do will ever matter"
"All of these games are based on The Great Impossible Thing to Believe Before Breakfast: that the GM may be defined as the author of the ongoing story, and, simultaneously, the players may determine the actions of the characters as the story's protagonists. This is impossible. It's even absurd. However, game after game, introduction after introduction, and discussion after discussion, it is repeated. "
"The GM is the author of the story and the players direct the actions of the protagonists." Widely repeated across many role-playing texts. Neither sub-clause in the sentence is possible in the presence of the other. See Narrativism: Story Now.