Recently, I was flipping channels and happened to come across a dramatized documentary on the History Channel called The Men Who Built America. It's a mesmerizig account of the early titans of American industry, and is hands-down one of the best documentaries I've ever seen.
It tells the story of men like Cornelius Vanderbilt and John D. Rockefeller, who built massive business empires (and mindboggling fortunes). Setting aside their sheer ruthlessness in many instances, the men in the documentary display certain characteristics that I believe are necessary for success in just about any business endeavor, whether it's a Fortune 100 company or simply your own self-publishing business.
Passion
You have to have passion for what you're doing. It should incite and excite a fervor in you. Thus, if you're an author, the thought of writing a book - having a finished tome out there - is something that should get your blood pumping. I'm not saying that every part of the process is going to be fun - some of it will be hard and downright frustrating - but writing should be something of a thrill.
Vision
I believe that vision doesn't just mean having an idea of where you want to end up; it also means seeing the possibilities. For instance, when Rockefeller got into the oil business, it was a fractured industry with numerous competitors. However, Rockefeller realized early on what it could be and set about consolidating the industry, ventually bringing something like 90% of the U.S. oil business under one roof. (Yes, it became a monopoly that the government eventually busted up, but Rockefeller saw the potential and worked to make it happen.) As another testament to his vision, rather than discard petroleum by-products that came out of the refinery process (like many did back then), Rockefeller invested in R&D to find ways to use them.
Likewise, authors should try to be visionaries. For example, we need to be able to see all the possibilities that extend from our writing - e.g., publishing in print, audiobooks, etc.
Drive
One of the things that really impressed me about the men in the documentary was their unceasing motivation. They simply refused to be thwarted in terms of their goals. When Andrew Carnegie was commissioned to build a bridge across the Mississippi River, most people said it couldn't be done. (I believe the tensile strength of iron, which was typically used for such projects, was too weak.) Carnegie thought it the project would work using steel, but it was incredibly expensive to make. However, Carnegie wouldn't give up, and he hunted around until he found a viable steel-making process.
Frome the stance of being a writer, I view drive as simply pushing on towards your goal, even in the face of adversity. Maybe you aren't selling a lot of books. Maybe you want to be traditionally published and can't find an agent. Maybe you just can't finish what you started in terms of writing projects. Regardless of those things, you should keep on writing, keep pushng through and trying to find success.
In retrospect, there are actually a lot of traits that people like Vanderbilt, Rockefeller and the like displayed: they hired top talent. They believed in themselves. They never stopped trying to move forward. I think these qualities are applicable to business in general, but certainly to writers trying to build a self-publishing business (or empire).