The pressure point.

The pressure always seems to increase when you get near the end of a book.  It's important you get it right, of course.  The ending is what most people are going to remember about your book.

But it's also because the book becomes more real.  It's all well and good when you're writing the earlier chapters, and the whole thing seems a distant possibility.  You're so far from the end, you don't worry.

But now, it's like you know you have the lead in a ski race and you don't want to make a mistake on those final few gates.

Problem is, by trying so hard not to make a mistake, you psyche yourself into making a mistake.

About this point in a book, I start telling myself that I'll need to rewrite, that I'm a long way from the end. 

Just to get me past the pressure point.