In 2018, only 16 percent of participants in the Goodreads Reading Challenge actually completed it, finishing 21 percent of the total books pledged. In earlier years of the challenge, those stats were sometimes higher—in 2011, 29 percent of participants finished the challenge, and in 2013, participants read 56 percent of the books pledged. This could be because in the early days of the challenge, only the most hard-core readers were participating—Goodreads started actively promoting the challenge to its users in 2015. But Suzanne Skyvara, a spokesperson for Goodreads, told me that the company doesn’t have data on what affects whether someone completes the challenge, and declined to speculate, saying the site prefers to focus on the fact that people are reading at all.

Still, the fact remains, more and more people are making reading goals that most of them will not meet. Why set yourself an unattainable goal? Why quantify your leisure reading at all?

Perhaps the most intuitive reason is the most common: Adding some structure to your reading life can be a way of making sure that you actually read. In 2011 and 2012, Donalyn Miller, a reading ambassador with Scholastic and the author of two books about reading habits, conducted a survey of adult readers’ practices, trying to figure out what keeps people reading when they no longer have the structural support of having to read for school. One of the key things she found was that “the only difference between a nonreader and a reader is that a reader has a plan for future reading and a nonreader does not,” she told me. It’s easy enough for reading to fall by the wayside with the responsibilities of adult life and the on-demand pleasures of Netflix and the like. “A plan for future reading” might just mean putting books one is interested in on hold at the library, or a loose plan to dedicate more time for reading. Or it might mean a yearly reading challenge.

Ben Gosbee, a 31-year-old accountant in Beverly, Massachusetts, says he read all the time as a kid, but noticed that in recent years he hadn’t been reading much. So he set a goal of reading 25 books this year. The number, he told me, is “something concrete to focus on”—he fears that if he had instead made his goal to read a little bit every day, he would have found excuses not to. As an accountant, he said, he’s very “numbers-oriented—I enjoy that kind of organization and sorting through data.”

Attainable reading goals can be motivating and improve the experience of reading, according to Neil Lewis Jr., a professor of psychology at Cornell University who studies motivation and goal pursuit. But “if the goal is unrealistic (given the realities of the person’s life) then it could actually be demotivating,” he told me in an email. “When people set goals like this, we often forget to take into account the other things that usually occupy our time and get in the way … If you have not been reading as much as you would like, it is probably because you are doing other things instead; are you willing to scale back on some of those things to make time for more reading?”