There are a lot of different reasons to use a pen name. The obvious one being that people can’t say, spell, or remember your real name. I also know some authors who use a pseudonym because of a conflict with their day job. For example, one such author writes dark, bloody horror novels by night and is an assistant principal by day. There are other authors who change names in order to re-invent themselves and escape a poor record of sales under a separate alias. But yet another great reason to do so is because you want to explore multiple genres.
The publishing industry wants authors to be established as a brand just like any other product. They want people to be able to pick up any Ethan Cross novel and know what to expect. It’s a sound business principle. It’s kind of like the concept of Pepsi versus Mountain Dew. If you opened up a Pepsi and it tasted like Mountain Dew, you would probably be shocked and disappointed. You may even like Mountain Dew, but you sat down expecting a Pepsi since that’s what you bought. It’s the same idea with an author. I want readers to pick up an Ethan Cross novel and be able to count on a breathless, fast-paced suspense thriller. I do plan, however, on writing books in several different genres including action/adventure, science fiction, literary fiction, horror, fantasy, or whatever good idea comes along. I love all types of books and stories and have ideas that don’t fit into one type of box. But those ideas will fit into a box because they will be under different names. So nobody will buy an Ethan Cross book and get a bad taste in their mouth expecting Pepsi but receiving Mountain Dew instead.
However, many authors do get away with writing in multiple genres under a single name. Others brand each book as a certain type with the packaging and titles but leave the books under one name. Both scenarios – using a separate name or a unified name – present different problems. Use one name, people may be disappointed with what they get. Use multiple names, people may not discover your writings in another genre that they would equally enjoy. As with almost anything else, there are no steadfast rules. I think in this regard the rule of thumb is simple…we each have to find what works for us.