I guess one prerequisite of success (or SUCCESS!) is people liking your work, but I'd suggest that getting a publisher behind you is at least as important.
Why did Peter V Brett and Patrick Rothfuss both shoot to fame after their first publication? Yes, their stuff was good, but so it a lot of work that's never such a huge success. The crucial thing was solid advertising, well planned signings, and general backing.
Equally, Joe Abercrombie's latest book was good, but it was a huge hit because Gollancz ploughed money in, getting the book everywhere including Tesco!!
I don't see how to get this kind of exposure with e-publishing, no matter how much your readers like the work.
Corgam.
It's true that ultimately to get exposure you need to market heavily, but the fact is publishers aren't going to spend much on marketing a new unproven writer, so even via the traditional route you'll have to do most of the leg work your self, and you can be screwed if your publisher makes stupid decisions like picking a bad book cover (as a new writer you'll get zero control over it).
Thanks to the internet, it's
possible to get an enormous amount of exposure yourself. It will take time and effort and money, but it's possible.
Ultimately it's going to come down to what resources an individual writer has available to them. Some people have great resources that actually enable them to do things a publisher wouldn't do.
A good example for my own work is book trailers. Anyone can upload a book trailer to youtube, and having a good understanding of how keywords work will put your trailer to the fore.
If you check them out, most book trailers are terrible. Seriously terrible. Ones from official publishers really aren't any better. For most people, that's probably the limit of what they can pull off.
But I happen to be a filmmaker myself. I work in the film industry, and my friends count amongst some of the most talented technicians and artists in the world.
My book trailers have the potential to be far, far better than 99% of anything else out there - either self-made or from publishers. That's a unique resource I have at my disposal, and I'm going to exploit it to its absolute maximum. If I do it right, it has the potential to be enormously successful. This is particular relevant because my country seems particularly switched onto online media and social media; it's relatively common for viral videos to take off and become cultural memes, often garnering their own articles on the national news.
That's one way ePublishing benefits me more than traditional publishing. Another way traditional publishing is a negative is that New Zealand is a very small local market for traditional publishing. The choice for local publishers is very small, and the runs are tiny (HarperCollins is essentially the
only option I have for local publishers). My options are the slow crawl from NZ to Australia and finally into the UK, Canada and US where I might make some money, or to try my luck at overseas publishers (which I am actually doing as well, incidentally). But overseas publishers generally don't look as fondly on foreign writers, and even if I do get accepted it essentially rules out the typical traditional method of marketing which is signings etc. as I have neither the time nor the money to travel to the US or UK.
A quick disclaimer, however:
It probably comes across like I think self-publishing is
the answer but that's not really what I think at all. What I am saying is that the climate has changed, and
under the right circumstances ePublishing your own work can be a better option that traditional publishing.
That's not going to apply to everyone, and every book. But it certainly applies to me, and it's only going to continue to apply to more and more people, which means if we want to keep up with the play we need to readjust our opinions on "vanity publishing".
Anyone wanting to automatically dismiss all self-publishing as vanity publishing should try make the argument to Amanda Hocking that she would have been better off spending a couple of years trying to get a publisher to accept her books.