Well, there's actually a story behind that.
In Greek mythology, the hero Theseus has to find his way through the Labyrinth of Crete so he can face the Minotaur. However, the labyrinth is so brilliant and so complicated that nobody has ever been able to make it all the way through. How will Theseus confront this task?
Well, being mythology, he doesn't just put his hand on the left wall and start walking. Instead, he gets a magical gift--a golden ball or spool of thread that will show him the way through the maze. All he has to do is follow it, continually winding it up, and he will find his way through.
Guess who gives it to him?
Ariadne, the daughter of the king of Crete, determined to get Theseus through the maze. Thus, that name is really fitting to the maze-builder in Inception: the Architect, as they call her.
Well, an interesting tidbit, no doubt, and maybe I've "enriched your viewing experience" for the next time you watch Inception, but did that have a point?
Yes. Yes, it did.
My point was this:
That's how story is for me.
I'm in this labyrinth, and it's dark, and I look around, and I suddenly catch a glimmer of that golden thread. It's showing me the best, most complete, most wonderful way through the maze of passageways. I move toward it in the dark, and it's lost to my view, but I head in that direction and do my best to find it and catch hold of it. Sometimes I don't get hold of the thread right away. Sometimes even after I get hold of it, inching my way through the dark, I suddenly lose the thin fiber--it slips from between my fingers and I have to stumble around for a moment. But if I just keep trying to find that golden thread, the maze of possibilities of what a story can be suddenly transforms into one path of what the story should be.
And for everybody, that thread is probably different--or at least, it leads them on a slightly different path. If not, where would the joy be in telling and retelling stories? But wherever that thread leads is where you have to go, otherwise you waste your time. Ironing out a story is about paring down from the infinite possibilities into one path--hopefully the best path, the one that will impact the audience member the most (for good). That golden thread is hard to find, but it's worth searching for, because it will make your life easier and your story better. It takes time and patience and a lot of listening and thinking and trying things that don't work, but it gets you there, and it's the best route.
That's how it is for me, anyway.