It's hard to choose just one of the three things that I think are best about being a writer. If you are a historian, doing the research is a great pleasure. I love searching for relevant books and sitting down with a stack of them next to me. The second thing, and it's equally important, is happy readers. If someone says "I found it hard to put down" then I know I've succeeded. And thirdly, the characters themselves. I like it when they do something that surprises me, and that happens quite a lot.