Paperbacks revolutionized American reading habits when they first appeared in the 1930s. The softcover "pocket books" were cheaper to print, cheaper to buy, and easier to transport than the bulky hardcovers that had previously dominated bookstores. By 1960, paperbacks were the preferred book format of readers.

Despite their popularity, it's still impossible to find paperback versions of many new books when they debut. It's a common practice among publishers to release new titles as hardcovers and publish the paperback edition about a year after the initial print run. People who do their reading at the beach or on the subway may not be happy about it, but the financial benefits of this model mean it likely isn't going away any time soon

"While a hardcover book is more expensive to print than a paperback, the publisher does traditionally make more money on that edition, allowing them to earn back the author's advance and the costs they incurred for printing, shipping, marketing, and distribution," Dinah Dunn, a partner at the book packager Indelible Editions, tells Mental Floss.

Hardcovers may be more expensive to produce than paperbacks, but they still cost just a few dollars to print. Publishers can then sell them for upwards of $30 and rake in enormous profits.

Cheaper paperbacks are more popular with consumers, accounting for roughly 80 percent of all print book sales, but when a book is still new, sellers can count on certain readers to pay more for the hardback. "An author's fans are willing to pay the higher price in order to get the book when it is first published," Dunn says.

The fact that it's the only print option for the first months of a book's life isn't the format's only appeal. While paperbacks have lost much of the stigma once attached to them, they still can't match the built-in importance of a hefty hardcover. "There is also a level of prestige attached to a hardcover versus a paperback, as it [shows] a commitment by the publisher to the work," Dunn says. "Hardcovers are also more often reviewed and considered for awards and are more often ordered by libraries." Hardcovers have a more commanding visual presence as well, and they're easier for bookstores to display.

After sitting out a book's initial print run, paperbacks do ultimately benefit from arriving late to the party—as do publishers and booksellers. Releasing the paperback edition a year after a book debuts is an excuse for another big publication event. That means publishers can drum up fresh excitement around a title around the time that sales are usually starting to peter out. Frugal, practical readers eventually get to buy their preferred version of the book, but only after the hardcover has been milked for as much revenue as possible.

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