GM: Alright, Peter. You've split from the party and gone to persuade the druid to come down from the tower.
Denny: You've got this, Peter!
Johnny: Yeah, you have the highest Persuasion score out of all of us.
Peter: Thanks, guys. Alright. I approach the druid and try to appeal to the good within him.
GM: Before you can, the druid tempts you with some herbs to calm you down. Make a Wisdom roll.
Peter: (Rolls high on the Wisdom roll) Nice! Pretty sure I resist the temptation.
GM: You do. What do you say to persuade him to come down?
Peter: I'm going to confront him about his the deception against the rest of my party members.
GM: Alrighty. Make a Persuasion roll, please.
Peter: (Once again rolls very high) I am on a roll! So, does he confess to his treachery?
GM: (Hesitates, having expected this social encounter to be more severe than it's played out)... No!
Peter: Wait, what?
GM: The druid is offended that you would accuse him of such a thing. He attempts to grapple you. If you don't break his hold, he may throw you from the tower!
Peter: What? Is he nuts?
Denny: I did NOT see this coming.
GM: Make a Strength roll against the druid!
(Both roll dice, the GM for the druid and Peter for his character. Peter rolls below average. The GM glances at his dice. He's rolled extremely high.)
GM: You are flung from the tower and, after a few seconds, hit the ground with a sickening splat. I'm sorry, Peter, but your character is dead.
Johnny: You must be kidding, aren't you!?
GM: Nuh-uh! Look! See? (lifts GM screen to reveal his high dice roll to the players)
Peter: What the hell, man? I resisted his herbs, rolled an awesome Persuasion roll, then he up and tosses me off the tower?
Denny: Yeah. And we sent Peter because the druid didn't seem to be a violent guy. We never would have let him go up there without back up if we thought the druid was going to want a fight!
GM: Well... uh... that's just... that's just the way it goes. I'm the GM, so there!
(Johnny, Denny, and Peter sit silently glaring at the GM. The GM pretends to shuffle some papers and arrange his dice, unable to meet the eyes of his players.)
GM: So... Johnny. What is your character up to?...
Sometimes, as GM's, we don't quite get the outcomes for which we plan. Actually, that's an understatement: very often we find that despite all of our planning, our clever players concoct a plan that totally bypasses all the hard work you put into planning the session. All we can do in response is roll with it. However, there are some times when you're counting on a certain turn of events to occur and, despite the meticulous planning and otherworldly luck of your players, you decide to use your GM powers to inject your machinations artificially.
In the above example, the GM is hoping for a more severe confrontation than the way it is playing out with Peter's character. In an attempt to have things go his way, the GM artificially injects drama into the scene by causing the druid non-player character physically assault Peter's character, despite the fact that the druid has not exhibited violent tendencies in the past. The result of this encounter is that Peter's character is unceremoniously tossed over the edge of the tower and falls to his death.
It is good player etiquette to respect the GM's ruling and decisions. However, in this case, the players are right to call into question the events on the tower. As a result of being called out, falls back to the good old because-I-said-so defense: a defense that should never be accepted by anyone under any circumstance. If the GM (or any other authority figure) is unable to back up their decisions with a reasonable explanation, that person is unsuitable to uphold that decision. Heck, even an unreasonable explanation would be (marginally) easier to swallow than the non-answer of "because I said so."
The GM's position is further compromised when he reveals to the others that he did indeed roll high enough to beat Peter's Strength roll, feigning impartiality. The players are not so easily satisfied though. After the revelation of the dice roll, Denny points out that the druid had not previously acted violently towards them, implying that the act of violence was not planned and dispelling any ideas of impartiality.
His poorly hidden attempt at railroading revealed, the GM has an important decision to make, as only he has the power to make it: Do we retcon the previous scene and have the druid quietly and come down from atop the tower or do I put my foot down and tell my players that it is what it is? While, as the GM, it's totally within his rights to tell his players to suck it up or not play, and certainly there are reasonable arguments for such a decision, the former is likely the best course of action. It may, however, be the more difficult of the two, for it requires one to do something quite difficult, especially for a person with as much responsibility as the GM: admit to being wrong.
If the GM is strong enough to admit to having made a poor decision, the benefits are significant. First of all, he has begun to regain the trust of his players.This breach of trust may not be fully repaired, but at least the players know that their GM is able to admit to his mistakes and is willing to take the steps necessary to rectify them. Secondly, the GM is able to see that he is not infallible. This potential introspection can teach the GM how be a better GM and how to better act should a similar situation present itself in the future. Thirdly, the game is, once again, cooperative storytelling. One of the core aspects of playing an RPG is chance to come together and create and participate in a story. If the GM were to just shut down any and all attempts from the players to move the story in a direction other than that envisioned by the GM, it is no longer cooperative storytelling and the GM may as well be telling the story to the players, now relegated to listeners of the GM's tale. As a result, if the GM is lucky, his yarn will be half as entertaining as it would have been with the input of both the players and raw luck (or lack thereof).
Accountability at your game table can potentially lead to you being more accountable in your everyday life. People may more likely to see you as responsible and trustworthy if you are willing to admit that you goofed instead of just pretending like you're doing fine and others just have to shut up and put up with your crap. Being able to admit to yourself that you've messed up can make you more aware of your mistakes and, therefore, hopefully less likely to repeat them. Instead of thinking you can accomplish what can be done with a team by your lonesome and wondering why the end result is so lackluster, accountability can help you and your collaborators get back on track to making something truly noteworthy.
Maybe some times, we feel we know everything and that we have a great and grand story to tell and that we don't need other people telling us how it should be different. Some times the dice beg to differ. And some times, when it's all said and done and if we're sensitive to others and willing to admit our faults, we can step back and behold some damn good stories that dwarf any sort of tale we may have come up with on our own.