There is a certain part of the book when you realize that there are only a few chapters left until you are done. (Fair warning, a certain red-head may be at this part of her book.) Ahem, as I was saying:
When you are a writer and you get to this part of your book, you sit down with your calculator and start crunching numbers to figure out, realistically, how quickly you could actually be finished with the first draft.
Then you sit there and look at the calculator a bit. And then you think, "Hm, if I can write 1,000 words four days a week, that means I can get 4,000 words a week. That would have the rough draft done in two weeks."
Wouldn't that be nice? Two weeks!
Then you pick up the calculator again. Okay, so if I work through lunch and then work at home in the evenings, maybe I could get 2,000 words per day. If I could do that for just five days, I would totally be finished!"
Then your realize, "If I call in sick, I could work for eight hours straight. I could have it all FINISHED in one day!"
Just eight solid hours! How hard could it be?
Then you check your email...and Facebook...and Twitter. You get some chocolate, and try to remember the name of that movie from the late seventies that ends with the shot of people standing on the back of a giant sea turtle.
Suddenly two weeks sounds just fine.
Or maybe the three week option...that one was good, too.