Formulaic stories work. The old boy meets girl, boy falls for girl, boy loses girl, boy gets girl back, is a formula that has served books and movies well for....well, even Shakespeare was in on the game.
As an audience, when we see a set of circumstances, we begin to have certain expectations. We know the formula and connect the dots. Which is fine. There is a certain comfort to be had from knowing what your'e going to get. You just know that if the boy screws up his relationship then either he'll do something fantastic and get the girl back OR realize that the girl he was chasing wasn't the girl he really wanted. As an audience, we expect those things.
As writers then, our job is to give the audience what they want but some how manage to subvert those expectations, giving them something fresh.
This weekend, I saw the movie Bridesmaids. First off, it was hilarious. I haven't laughed that hard or that loud during a movie in forever. And I wasn't alone. There was a mom and her daughter in front of me, howling. There were a group of guys cracking up. The movie appealed to every age, gender, race. It was that good.
I won't give any of the plot away, but at about 2/3 of the way through the movie, I said to myself that A would happen, leading to B and then C. Well, we got C but not even remotely as I'd imagined. We kind of got B too but it looked more like M. Not sure what I'm talking about? Neither am I. Okay, seriously. If this movie had been a regular formulaic summer movie, A, B, and C would have happened and I would have left with a smile. But the writers of the movie gave into my expectations but subverted the route we took to get there in a satisfying, hilarious way that turned out to be better than I could have hoped. That's what's making this movie a word-of-mouth blockbuster instead of just another throwaway romcom..
People always say that it's not the destination but the journey. That's also true in writing. The destination id definitely important but the journey you take to get to the end can determine whether you're book is good or whether it's Bridesmaids.
Oh, and it wasn't just me. I was telling M about my expectations after and he chimed in, that he'd thought the same thing was going to happen. Those formulas are so burned into our minds that everyone recognizes them.