We all know someone in our niche with phenomenal sales, the one author who has rocketed to the top with no more talent than you have. The difference is probably your book marketing campaigns. Most authors are hard working, spending days on end from morning until night, doing everything they can to get their books in front of as many readers as possible. And then there's that small percentage that skate on the edge, using black hat marketing techniques. Black hat marketing is a series of book promotions or techniques that, while not exactly illegal, are somewhat sleazy and smack of cheating the system. There's no denying the fact that they get results, at least in the beginning, but many times publishers end up pulling accounts when they discover the marketing techniques being used. Are you doing the right kind of marketing, or is your hat turning black? 
Sock Puppets
Sock puppets are imaginary reviewers that either praise a book or give a bad review to an author's competition. The publishing world was turned on its head in 2012 when a series of authors were proven to have bought hundreds of reviews for their books and against others in their genre. The fake book reviews helped the books climb the rankings on book sales, which resulted in increased sales for the guilty authors. Sock puppetry can be as simple as asking your sister to give a bad review to someone above you on the rankings list to going on Fiverr and buying one of the dozens of gigs that promise a certain number of positive reviews on your book. Some authors got their accounts pulled early in 2015 when Amazon found they were in Facebook review circles. Each member of the group would review the new book from everyone else in the circle.
Purchase Circles
The way Amazon and other online retailers work is that the more copies of your book that sell, the higher relative ranking you'll have, in general. The higher the ranking, the more sales a book will get, on average. It's a self-perpetuating circle. As an added bonus, when a book reaches a certain height in the rankings, Amazon will begin to promo the book on their own with no help from the author needed. All that's needed to start this rise is a large number of books purchased the first couple of days after its published. Purchase circles work like review circles, in that every member buys copies of every other member's books. The specific reason for these groups is to game the system and make the books rise higher in the rankings. Not against the rules, but definitely on the shady side.
Big Volume
The larger an author's catalog, the more a reader will trust that author and buy his books. This is true in non-fiction as well as fiction books. Some of the blackest of the black hats are farming out book titles to writers overseas, paying them a small amount to write a short book, often no more than 20 pages. These people publish badly-written books, often one or more a day, creating huge catalogs and creating the image of expertise in their genre. It only works for a little while until the reviews catch up with them, but the money can be great until then. The only loser is the readers, and other authors who can't get readers to try their unknown work.
Spamming
Everyone uses social media for marketing, but black hat operators create dozens of fake profiles designed solely to spam groups with their sales pitches. They create dozens or hundreds of fake accounts each day, and when Facebook or Twitter shuts them down they just move on and create more the next day.
Keep the Faith and May the Force be with You!
