Being an author means you need to create a brand for yourself. No, not DOUBLE R-BAR, or LAZY W, but the idea is exactly the same. Your author brand is your name or pen name. It is used primarily to promote sales of your books once your brand has become familiar among readers.
Take a well-known product; how about Dodge Ram? We all know certain things about it when we hear the name. For instance, we know it's a truck. We know it has a ram's head as its logo. We know that logo appears on the front of every Dodge Ram truck. We figure it must be a pretty good truck because they do a lot advertising, enough in fact, that its name has become common. That's the same thing you want to achieve as an author. People, in general, feel that exposure equals quality. So if you can accomplish exposing your name--your brand--in enough places, you'ill most likely be considered an author whose books are worth purchasing.
As an example, let's consider author Mark Twain--that's his brand. His real name was Samuel Clemens; Mark Twain was his pen name, and that was the name that gave him his brand. People became familiar with his brand and began to trust that it indicated something good (or something bad if it had happened to obtain a bad reputation. Don't let that happen). In the case of Mark Twain, familiarity with the name meant purchasers could depend on having a good read when they chose to buy his books. That's exactly what you want to happen.
If your name is John Smith (a perfectly good name, by the way, but rather common) you might want to consider a pen name so it will grab people's attention. PLEASE don't skate on the name of another famous writer, however. In other words, if your name is John Steinbeck, don't promote yourself by that name; choose a pen name. It will actually do you more harm than good to try and make readers think you are the famous author instead of yourself just to sell books. After all, you have your own style, and that needs to shine through. And who knows...you might actually become a more prosperous author than he was!