Authors often depend on their social media accounts as advertising tools, hoping to gain fame and sales from their posts. The more followers, the better the chances that advertised products—in this case, books—will sell successfully. But it turns out that having millions of followers is still not a guarantee of a rise in sales when authors or celebrities post about books, which is puzzling given the usual advertisement history within social media. To all appearances, there should be a correlation between the number of followers one has and the number of books a person would sell, particularly when compared to other products when their gain in popularity or their sales numbers reliably skyrockets just from one post. But not books. What is behind this mystery?

Let’s take Billie Eilish as an example. A celebrity with nearly a hundred million followers on Instagram and six million more on Twitter easily could sell millions of books, right? Yet, her self-titled book, Billie Eilish sold about sixty-four thousand copies, according to NPD BookScan, a number much lower than expected, given the number of fans and followers she has all over the world. According to the New York Times:

Every book is different, an individual work of art or culture, so when the publishing industry tries to forecast demand for new titles, it is, however thoughtfully, guessing. Because there are so few reliable metrics to look at, social-media followings have become some of the main data points publishers use to try to make their guesses more educated.

The number of followers can greatly influence the decision of publishers or their willingness to pay an advance for a book deal. Sadly, followers are seen more and more as unpredictable gauges when it comes to book sales.

It is important for publishers to consider an author’s platform, including social media, radio shows, YouTube channels, or guest appearances on TV. There could be several reasons why a large social media platform does not equal substantial book sales. Let’s examine three types of authors: the first group has the more traditional authors whose main occupation is writing; the second group includes established celebrities and movie stars; the third, a younger generation of singers or influencers. It is usually the second and third groups that have a larger social media following. It could be that their followers mostly consist of people interested solely in their music or movies and other products these fledgling influencers advertise, such as cosmetics or clothes or other items they find interesting and share with their followers. Reading might not be the followers’ favorite pastime, so when celebrities post about their books, if it’s not the right audience at the right time, the books simply won’t sell the projected number of copies.

For the sake of comparison, we will look at a few celebrities and examine their book sales numbers to demonstrate that a large social media presence is not a guaranteed success when it comes to book sales. In addition to Billie Eilish, Justin Timberlake, with fifty-three million followers, sold about one hundred thousand copies of his book Hindsight in the last three years. Tamika D. Mallory, with around one million followers, sold about twenty-six thousand copies of her book, despite getting paid over one million for a two-book deal. Publishers are in a constant state of wonder about followers. How engaged are they? How much attention do they actually pay to posts? There is an increasing awareness about followers not being as engaged with posts in general.

Furthermore, it is sometimes the celebrities themselves who might not be as engaged with their books and, therefore, with their posts. It’s not enough just to post; some book contracts now specify how many posts are expected or required from the author in order to engage followers more. Also necessary are frequent and heartfelt explanations on why the book was written, how it fits into the authors’ lives, what they hope to gain by publishing this book, and what inspired them; all those things can further penetrate the surface when followers look at posts, and they might be able to relate more to the books if the posts have emotional elements woven into them. Authors and publishers tread the murky waters of social media, hoping that somewhere between traditional and innovative advertisement their gamble will pay off.