I outline, and everyone I know who came from screenwriting does the same. I'm not saying it's the "right" way to do it, but it's my way. I have my own quirks, as everyone does. Yes, we're all special little snowflakes. Now that we got that out of the way, I get a little annoyed at the occasional (read as: not everyone does it so calm the fuck down before you get offended at my opinion) but the occasional attitude of the non-outliner, or write-by-the-seat-of-the-pants people. I get the feeling, now and then, that they think this is a more "real" way of writing. Like I use an outline as a crutch. Like I'm stifling my creativity by forcing myself to adhere to a predetermined structure.
So, without endorsing this as the way you should do it, because you should write however the hell you want to, and because I think 99.9% of all writing advice is bullshit and absolutely 100% of all unsolicited writing advice is dangerous, toxic bullshit you should avoid like a glowing meteor that fell in your yard - here's why I think outlining is better.
First: The truth is, at some point, it's all made up out of the ether. We're all "pantsing" it. It's what making up a story is. Whether I do it and then write down those snippets of ideas and form it into a structure and work out plot holes, narrative inconsistencies and character before I start writing chapter headings doesn't mean at some point I was just riffing and making shit up.
I have strange ways of working on my ideas and forming outlines. I like to think about a story for a long time before I formally write it all down, but it's all part of the writing process. I hit on an idea and I roll it around for a while. If it sticks with me I know I'm on to something, and really my only criteria is if it is a book I'd like to read. Well, the only way I'm going to get to read that book is if I write it so . . . off I go.
But I still think on it. I think before I take notes. Then I write some stuff down, longhand. When it seems like a real story and not something I'm going to get to 20K words and find I've used up my story, then I set down to do a real outline.
Second: Outlines are flexible.
My outlines are fairly sparse. 'He goes to the apartment' may end up as a 3K word chapter. And they are flexible. This myth the pantsers have that outliners sit with a ruler and stick to what they've outlined as if we were German SS troops who must stick to zee outline at all costs! Not how it works. If the story takes a different direction, then great.
I knew a guy who was working on his first novel and he told me he had about 70 pages of notes and outlines. To me, that's excessive. But again, it's your process, man. Do your thing.
Third: I don't like to rewrite.
I don't really know anyone who does. A lot of writers will say this is where the "real" writing takes place, but I disagree.
And since I outline, since I don't meander toward a story, I do very little rewriting. I rewrite for polish, for grammar, to fix mistakes in my own inadequate language skills and punctuation bugaboos.
So if you don't outline, you don't get to complain about how painful your rewrites are and lament on how you had to toss out all of chapter 4 and start again.
Four: since when is planning ahead a bad thing?
I think of it like remodeling a house. If you build the house, paint it, put the carpets in, decorate it and then step back to look and only then say, "Y'know what, that door should be over there." Well, shit, that's a hell of a lot harder to do than making the change from a guest bedroom to a padded sex dungeon when it's all studs and plywood.
I believe in pre-production. You iron out the kinks, you strive for consistency. Then you set down to the building. And it's not like the old Hitchcock thing where he allegedly said the actual shooting of a movie was boring because he had it all thought out beforehand. You might know where the story is going, but isn't the pleasure in writing the words, the sentence structure and finding the perfect way to describe that sound when a fat man falls down the stairs while wearing tap shoes?
Outlines don't stifle creativity. If anything, I think it frees me up to focus on the words because the plot is already sorted out.
So if you don't outline, keep on keeping on. But don't sneer at the outliners and treat us like we write with training wheels on.