My little brother hated English class. One of the reasons for this was that he had the bad luck of being assigned to about four straight years of uninspiring teachers, but another was that he hated being asked why a character did something or what they might have been thinking on essays and tests. “They can’t think anything!” he would grumble. “They don’t exist.” The most captivating stories for him were always ones like Lone Survivor, written about real-world events and people, because he could appreciate their reality and truly engage with their characters. To Harry, the characters in a made-up story distinctly aren’t real, and the marks on the page are just the work of an author, not a window into a world of its own.
For casual readers of books, this way of looking at characters, if a bit less magical than the alternative, is perfectly alright. It’s also reasonably popular way to look at stories. After all, in the strictest sense it's true. Characters and places and events in fictions technically don't exist, and really can’t be said to want or pursue anything. It really is, a reader can tell you, all the author’s imagination, and the only person who can be said to have any agenda is the writer of the tale. As a reader, I could still enjoy a story immensely if read it, finished it, and believed that the characters simply ceased to exist after the end of the final page.
For a writer, however, this way of thinking simply isn’t an option. In creating the characters they're writing about authors might be able to conceive of them not existing, but only for those few few moments of storytelling. Once the characters exist, all an author can do is follow them, watch their desires clash and play out while recording. To wrest control of the action from your characters, to step in and choose the course of the tale instead of simply following the personalities, is to insert the author where an author doesn’t belong, where he or she should only see and hear and be neither seen nor heard. If you want to create stories that feel honest, in other words, your characters have to be the ones driving the action, not you. This, in turn requires that your characters really exist, that they have enough reality in them to drive action.
This is, obviously, a difficult thing to do. It requires writers to step back form our work, to say not “what do I want to happen here?” but rather “what does my character want to happen here?” or “what would my character do here?” It forces us to take ourselves out of the equation which, as an author, is somewhat paradoxical. But at the end of the day, this is how we write good stories: by recognizing that the stories we write aren’t about us, but about the characters that live them.