Although I did once write the first draft of a novel in a month. A chapter a day every day until it was done. At the time it was a straight crime novel, set in the area where I lived. I did it for fun, but as I was an SF writer I didn't have anywhere to place it and I also had other books to write: books I'd already been paid to write. But after that first draft had been sitting in a folder for a couple of years, my then publishers arm-wrestled me into writing near future thrillers because they wanted to get out of the (according to them) dead-end no-hope SF business. So I took out the MSS and spent six months completely revising it, transcribing its setting to a near future London half-wrecked by terrorism, and it was published as Whole Wide World on September 9th 2001. So it goes.
Right now, I'm in the first stages of first draft limbo, which follows on from a long and shapeless period in which I made scads of notes and did about a metric ton of aimless research. And then I threw most of the notes and the research away, but at least it let me know what the thing isn't about. After that, I spent a few weeks footling around, trying out this and that move, trying to find the first foot- and handholds on the long climb upward to the nirvana of the last page.
Now, I have a rough idea of the shape of the plot. I've a fix on two of the main characters and after a couple of weeks I think I've got an idea or two about the third. For one thing, I know now that he's a first-person narrator, which after several false starts came as something of a surprise. Still, as John Cheever used to tell his creative writing students, you can't just jump into first-person narration; it has to be earned. Ahead of me lie all kinds of false starts, dead-ends, pointless detours, horrible mistakes, and futile attempts to avoid the sucking pits of cliche. One thing I've learned from writing novels is that writing the next one isn't easier. Wouldn't have it any other way.