The End. This is a tough one. When do you know when you've reached the end? Do you go for word count and once you pass it, you can finish the story? Or do you plot it out and when you reach a certain point, you're done? What if you aren't a plotter?
I have this bad habit of ending too abruptly, and I always have to go back later and add more so the ending is so harsh. I'm working on it though!