World-building is one of the most important and most difficult things that an author must do. In fantasy, world-building can be anything from elaborate Tolkien-esque building of an entire universe, to simply attempting to explain how magic works in your world, or explaining the culture or political structures of certain magical creatures. These sometimes seemingly minor details can add so much depth to storytelling.
However, many times I find world-building tends to be forgotten by authors who aren’t creating a whole new world. The idea that urban fantasy or modern fantasy doesn’t need as much world-building, because these magical characters live in our world, shows a lack of understanding of basic storytelling. TV shows and movies are the worst offenders when it comes to world-building, often relying some on special effects and fast-paced action scenes to tell a story, and as a result the viewer leaves entertained, maybe, but lacking insight into the world and characters they have just visited. Even books sometimes suffer from this. It’s been said by many authors that less than half of what you write or know about the world you created doesn’t end up in the actual book, because it would distract too much from the actual plot. Obviously, TV shows, books, and movies are not meant to act like history books; they are supposed to entertain, so sometimes the world-building gets put aside for action or romance. No matter how good an author is at balancing world-building and moving the plot forward, unanswered questions about how a universe works will always come up.
Other than porn and representation, I would argue that exploring world-building is one of the main reasons authors write and read fanfiction. They want to spend more time exploring the fictional world that they’ve only had a brief chance to enjoy. When reading Harry Potter, fans explored the Wizarding World with him, but only through his limited and often ignorant view. Furthermore, you can only explore that world through him; if you hear about something or see something in the story that you find interesting, you can’t leave Harry and read a side story about it—you have to stay with Harry. Then, after several hundred pages, you have to leave the world when you weren’t done exploring. Fanfiction allows a reader to continue to explore the world, perhaps with or without Harry. Not only that, but fans then get to contribute to building this universe in some way. Sometimes fans even do better than the source material at world-building.
One of the best examples of this, I think, comes from the Teen Wolf fandom. Teen Wolf is a very good show—I have written about it a lot, and enjoy it greatly—but the writers are so concerned with making the show action-packed that they barely have time to show their characters expressing emotions, let alone do any world-building.
If you really think about it (and obviously fanfic authors in the Teen Wolf fandom have), werewolves in the Teen Wolf universe would probably have a unique culture unto themselves that is different from humans. Pack dynamics would shape how they view each other, and their connection with the Druids would probably mean they follow pagan religious beliefs. All of these things help to build an interesting and unique magical world.
Even novels like Harry Potter, which do a pretty excellent job of building their magical world, can miss the opportunity to elaborate on the world because of the need to move the plot forward. One thing that I was always anxious to learn more about was the state of religious belief in the Harry Potter universe. We have already explored some possible Christian beliefs that exist in Harry Potter, but since wizards seem in many ways to have a very different culture from muggles, some fans have explored the idea of the Wizarding World maintaining pre-Christian pagan beliefs or mainly being devoted to gods of magic, like, for example, the goddess Hecate.
Magic in fantasy writing is great, but an author can’t just throw in a magical creature or some magical elements and call it world-building. They have to think of the implications surrounding those things. How would these magical things affect different cultures, societies, politics, and even more basic things like biology and home life? Some stories are lacking the world-building elements, and others just don’t have time to explore everything we are interested in. Thank goodness for fanfiction.