I've had it thrown at me from every direction that a writer must always outline at the very least the basic plot before going to work on the novel itself. How can you possibly get where you're going if you don't even know where you're headed? You can't get from Point A to Point B if there's no clear Point B to start with!
And here's what I say to that...
Get it? *wink*
I'm not saying jump in on a full-scale magnum opus with no idea what you plan on doing. I'm saying, don't worry about the road ahead, and just keep your eyes on what's in front of you.
Lemme share a few anecdotes from my "personal experiences" file. For the novel that I'm now re-writing, I spent a solid month picturing in my head exactly what was going to happen. I wrote every last detail down in a notebook, tore out the pages and carried them in my pocket, and stuck to that outline, not deviating from it in the slightest degree. Not once. Now, X amount of years later, I can read that first draft and see how stiff, forced, and unlikely it is (insofar as a fantasy novel can be "likely" in the first place). This is one of the reasons I'm now taking a second shot at it.
With the last three novels I've finished, there was no game plan. I had the bare framework of the story, the characters that would be populating it, a few ideas for some good scenes, and eventually a theme, and I ran with them. It's a given that there were roadblocks and times when I had no idea where the whole thing was going or what I was going to do next...also known as ruts in the road. Those times turned out to be the best ones, because that's when I had to really dig deep into my modest ingenuity and figure out how to save the situation and make the story better for it. And I think I succeeded in that, or so my trusty betas tell me. And because I just stood back and let things go as they would, there's no plot holes, the flow is smooth, and everything works in harmony...or so my betas tell me (can't judge my own performance, after all). The details worked out for themselves, with me only performing the task of actually writing them down and occasionally keeping them in line.
Put another way, think of plot as shrubbery. No, seriously. Outlines can turn out like topiary: The finished product may look interesting and pretty, but it's still tacky and unnatural. The end result should be more like a rose bush. It spreads, it roams, it ranges at will, and while you maintain it to keep it in check when you must, it has the freedom to grow. It's controlled chaos. That sounds bad, but "chaos" only means unpredictable--which is always a good thing when it comes to books.
Back to my original analogy. Which trips are the most memorable: the ones with the rigid schedules, where every minute is accounted for and allotted, or the ones with no schedule at all and you just follow where the road takes you because it just feels right? In my opinion, the process of writing a book should be every bit as enjoyable as reading one, if not more so. It's hard work, sure, but you also learn something as you go along, quite often about yourself. Corny as it sounds, it really is a journey of self-discovery. Why would you want to make a timeline for that?
Bottom line is, just don't sweat what's going to happen later and focus on where you are now. Let the next chapter take care of itself and, heck, if you can avoid it, don't even think about your big finish! Chances are, the story will take its own turn in another direction anyway. That's a good thing, though. It means its walking on its own legs!
Hope this helps! If not, disregard it as more hot air and hogwash!