"It's like driving a car at night. You never see further than your headlights, but you can make the whole journey that way. " --E.L. Doctorow, on writing
It's a question I see thrown around a lot, when it comes to writing: are you a plotter or a pantser? Do you need to know what happens ahead of time, or do you make it up as you go? It's an interesting question, in part because every single writer will have an answer. They may be firmly for one way or the other, or they may be somewhere in between (pants half up? pants half empty?). But they will be somewhere on that scale.
As for myself, I'm a plotter. I've written enough to know I have to plot, I have to know what's going to happen so I keep things going and bring the story to an end that makes sense. If I don't know where a story is going, then I have one of those wonderful attempts at a writing session where I'm staring at the mostly-blank page with maybe a sentence or two on the screen and no idea what the hell is going to happen next.
Granted, I get that sometimes even after plotting, but that usually means I screwed up somewhere. And then I have a plot to fall back on, so I can figure out what went wrong and keep moving.
I have tried to write stories by the seat of my pants, just taking an idea and a character and seeing where they go. One of the books I wrote in 2010 was like this -- it started off with a simple premise and an opening line about the world ending two weeks previous, and I was off and running. There was a kind of freedom to writing it, I have to admit. Not knowing where the story was going meant it could go anywhere. I filled the tale with all kinds of things, figuring that somewhere along the way, I'd learn how they all fit together. And in the end, the world was saved through use of a Ted Nugent song.
Looking back at it now, the book had plot holes large enough to drive the main characters' demon-horned armor-plated motorhome through. I attempted to rewrite the book, to take the story I'd made up as I went along and give it a real plot, and everything fell apart. Nothing worked when I tried to apply Earth Logic to it, and that's kind of essential for having a coherent story. The demon-horned motorhome does not excuse this fact.
As much fun as I had writing the book, and as much as I'd like to revisit the story with an actual plot set out ahead of time, it was a valuable learning experience. Over the past two years, I've put together a huge plot document for this tale, filled with a dozen and more ways to redo it, and I think I finally figured it out. Whenever I get back to the tale, I'll know what's going to happen, I'll have reasons behind everything, and in its own weird way, it will all make sense.
But it will read like I was writing it by the seat of my pants, if all goes well.
As for why things like the motorhome and rock music stopping the Big Bad were part of the story, that falls under the Rule of Cool, which I'll touch on next entry.