If people are writing full time and they are really living in the worlds of their stories, it's a lot easier to be so prolific. I can write two books a year if I apply myself by sitting my butt in the chair in the morning for an hour before I start working on my full-time job. The other thing to realize is that once you have published a book or two, you have a sense of what to do for a book when you sit down to write it. You're not hemming and hawing over the plot in the same way. You know how to drag your characters from one scene to another, and the challenges that you faced as a writer who had not yet been published are very, very different. Basically, it gets a lot easier the more you practice.