To know for sure how book reviews influence sales is hard to gauge. There are many factors that may lead people to purchase a book: boredom, amount of free time to fill, how long it’s been since their last pay day, an impending long train journey… However, there’s one thing that’s universal – both you and I would rather spend less than more. With multiple competing demands on our income, of course we want to be sure that the book we buy is worth the money. And reading reviews online is probably the quickest way to predict the ‘quality’ of a book.

Now, reviews surely come with their own set of drawbacks. There’s a chance that paid reviews may not be genuine; some people may not like the author in general or submit a review without even having finished the book first; and let’s not forget about the Internet trolls – people who are there just to hate.

However, there’s a solution to every problem. You can maintain the credibility of your book reviews by simply asking the readers to provide honest, detailed opinions, rather than a 5-star rating and a vague “I liked it”. Also, use well-known book review platforms, such as Goodreads, and don’t forget to mention that you’re open to negative reviews, too.

Now why should you want to go through this unpleasant process that might eventually backfire?

In short, reviews will help you reach more people. Not many authors realize how much marketing goes into publishing a book. It doesn’t matter whether you choose a traditional or self-publishing route, there’s always some marketing that you’ll need to do on your own. In the case of traditional publishing, the publisher is – technically – responsible for book promotion. But little do most authors know that most publishing houses invest most of their marketing budget in their most successful authors. (It’s unfair and it doesn’t make sense, I know, but that’s the business.) As for self-publishing, since you make all the calls, generating plenty of reviews can help you reduce the cost of hiring a marketing professional and is directly related to your book’s success.

So here’s our top six ways in which reviews can help you market your book and increase its sales.

  1. Reviews are science-approved.

Two Cornell sociologists published a paper in 2004, in which they reviewed recent qualitative studies and concluded that there was a positive causal relationship between review systems and sales. What this means, is books with more and better reviews sell significantly better than books without, and it is actually those reviews that cause the increase in sales.

  1. Readers look for peer approval.

Most readers seek opinions of people their age who have read the book and can tell if it’s any good. That way reviews attract more people, and thus more sales. But it’s a two-birds-one-stone situation because not only do they attract more people in general, but more of the right kind of people – your target audience.

  1. Look at Amazon.

Reviews are a fundamental part of this online giant. Look up any item on Amazon, and you’ll see star ratings featured right next to the name and image of the item. And what about those email reminders to leave a review that they send randomly every few weeks? If Amazon values feedback so much, who are we to doubt it?

  1. Reputation.

Book reviews help create an overall reputation for the author. The more positive reviews you get, the more credibility your ‘craft’ will gain and the more people will want to come back to read your next piece of work. And it’s no secret that the more well-known you are, the more readers you’ll draw in (just think about Stephen King and J.K. Rowling).

  1. People operate in averages.

It’s true for all of us, at all times. If we see that a book has an average of 4.5 stars – better yet, if the rating resulted from a few thousand reviews – we’re more likely to see it as a truly original story and so worth the money. In the case of non-fiction, especially how-to books, they’re more likely to seem practical and useful. Because thousands of people, with their different tastes and reading experience, can’t be wrong, right? (That is, if we forget about the extremes for a moment that mess with the reliability of the average – like in the case of 50 Shades of Grey, which people seemed to either love or absolutely hate.)

  1. Something to talk about.

You’ve been promoting your book left and right on Facebook and Twitter, and now you’ve found yourself with nothing to say. That’s when you can turn to the most positive reviews you’ve got and publish them as the content of your marketing posts. Additionally, these will further generate likes, comments and shares – all good for making your book more visible.

BONUS. Here are six more quick tips on how to start recruiting reviewers when you’re sitting with a nice round zero.

  1. Ask your beta-readers. They will be reading your book anyway, so might as well leave a review.
  2. Ask your blog subscribers, and Facebook friends, and Instagram followers, and Wattpad readers. Similarly, you can ask your friends to ask their friends to ask their friends to… You get the idea. It’s all about putting yourself, and your book, out there, and getting as many people involved as you can.
  3. Reach out to Amazon reviewers.
  4. Reach out to book bloggers.
  5. Submit your book to review sites (either paid or unpaid).
  6. And finally, leave a note at the back of your book to remind your readers that reviews are not only welcome, but strongly encouraged.