Recently on one of the writing forums that I visit, another author bemoaned the fact that they weren't getting many sales. (In truth, you can find many authors making this same statement across many forums - all day, every day.) As is typical in such situations, one of the first things that other posters in the forum pointed out was that the author's covers needed work. Basically, while the covers weren't completely horrible, it was difficult to look at them and get a sense of what the book was about: you couldn't decipher it from the image, the name of the series, or the novel's title. Others pointed out that, among other things, the blurbs needed work.
Needless to say, the cover and blurb are two of the primary lures by which you hook readers. If those aren't up to par, you're going to have a tough time gaining any traction. (It's not impossible, but you're likely to have an easier time teaching a fish to walk a tightrope.) Thus, it's a good idea to occasionally revisit the basics with respect to these elements.
When I was in the military, we had a 3-step process that was applied to any presentation that we were going to give:
1) Tell 'em what you're going to tell 'em.
2) Tell 'em.
3) Tell 'em what you told 'em.
I think the same concept applies to things like covers and blurbs. For instance, take the novel Seven Unholy Days by Jerry Hatchett.
First of all, there's the title. While Seven Unholy Days might refer to a number of things, the author follows this up with a subtitle: A Thriller. Once that's there, there's little doubt as to what the book's genre is.
Next, there's the image itself. All alone, it might put me in mind of something religious or perhaps a spiritual awakening of some sort; I might even come to the same conclusion when viewing it in conjunction with the words Seven Unholy Days. However, with the subtitle clearly indicating it's a thriller, it now makes me think of something apocalyptic. (And I won't even go into the fact that it's actually very nice cover art, because it's a given that we're all shooting for that.)
In short, the cover has clearly conveyed to me the genre of the book (spelled it out, in fact, which I have no problem with), and introduced an image that I can relate too on several levels. Frankly speaking, you can't ask for much more than that.
Moving on, there's the blurb. Without going into a lot of detail, it mentions things like a "ruthless maniac," the Book of Revelations, and Armageddon. In combination, those phrases shout action/adventure/thriller to me. Likewise, your blurb needs to convey the essence of your book - not just the genre but the overall conflict.
All in all, the author has done a great job of baiting the hook in my opinion. Good cover art, nice blurb, etc., all of which do their part in letting readers know what they'll be getting in exchange for their hard-earned dollars.
Basically, getting readers interested in your book is a lot like going on a blind date. Your cover is your headshot, and you really want it to be attractive and say something positive about you. Your blurb is your introduction, giving those who like what they see a little more insight into what you have to offer. Bearing those facts in mind, I'd encourage writers to make an investment in a great cover (like getting a professional headshot as opposed to photoshopping a grainy pic of yourself taken at a toga party in college). It may not be cheap, but it will be money well-spent - as is money for other things like editing/proofreading.
In all honesty, though - unless you are immensely talented in all areas of publishing (eg, cover art, editing, formatting, etc.) - I don't know how you can publish a book for less than several hundred dollars. (For those interested, I discuss a lot of the costs in another blog post: How to Beat the High Cost of [Indie] Publishing.) As the old adage goes, it takes money to make money, and you have to be willing to invest in yourself. (You could also raise funds on various platforms, but that's a post for a different day.) That said, you most certainly can have sales on a book with a bad cover, a poorly written blurb, and so on, although I wouldn't bank on it. To quote the film Inception, "[I]t's perfectly possible. It's just bloody difficult."
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