A great many people have pointed out just how much mere numbers miss the mark in education, politics, and business, but do they miss the mark in the world of books and publishing as well? I suspect, at least in some ways, that they do.
Is a book that sells a million copies necessarily a “good” book? That depends on what one means by good. Such a book is obviously good at entertaining readers if it sells that many copies, but it may not be, and probably isn’t, in terms of other “literary” qualities, in that the grammar and structure may be weak, and often there are great improbabilities in the background and economic/political structures of such books. But none of that matters all that much to the readers, especially if the book is fast-paced with an interesting plot, or if it has other qualities, such as sexual intrigue, overwhelming romance, or characters that suck the reader in.
By the same token, just because a book doesn’t sell well doesn’t mean it’s a bad book. It might not sell well because it’s been published by a small publisher, or because it’s a book about a character or situation that doesn’t have great appeal. It could even be a book by a major publisher and author with good reviews and those readers who liked it thought a great deal of it… but it just didn’t appeal to a larger audience. Then, it could just be a really bad book. There are some published. But the mere sales numbers say nothing, really, about why it didn’t sell more copies.
Even in the case of best-selling books, the numbers can be deceiving. A novel that sells 50,000 hardcover copies in a week will likely be near the top of the bestseller charts and possibly at the very top, even if total sales over its lifetime are only 150,000 copies in all formats, while a book that sells 30,000 copies a year for 25 years, but never a huge amount at any one time, will never appear on any bestseller list, yet will sell five times as many copies as the short-term wonder.
Publishers plan their publication schedules in hopes of maximizing sales. That’s why any given publisher’s top five authors seldom have new releases in the same month, and possibly not even in the same publishing season. Many consumers only have limited dollars for purchases, and the same is true of the book retailers, whether they’re Amazon or Barnes & Noble, or the local independent. So what’s available, and when, to the reader is in fact based on the numbers, and the interplay between what different publishers offer may result in higher or lower sales for the author, and the publisher. And first-time or midlist authors who release a book in the same genre or subgenre at the same as a mega-selling author may see their sales suffer somewhat, depending on how strong their reader base is, which, again, is not necessarily a reflection on how good the book is, but the numbers may make it harder to publish another book or may result in a comparatively lower advance on the next book.
There are some numbers whose impact I’ve never figured out, like the time when I was told one of my books was the best-seller of the month for the largest book wholesaler in the country. I’m guessing that meant that B&N and the brick and mortar retailers had under-ordered copies and the customer orders required getting immediate copies from the local distribution warehouse of the wholesaler… but that’s just a guess. And then there was the time when an ebook version of one of my books was in the top 100 in the Apple store serving Finland – just for a fraction of one day. That had to be a statistical fluke… I think.
So… take what all those numbers and what they mean with more than a grain of salt. The only semi-certain meaning is that more sales usually mean more money for the publisher, but not always all that much more for the author, at least if it’s a media tie-in novel.