We may be halfway through January already, but the spirit of new year is still in full swing over in San Francisco, where the 2014 Goodreads Reading Challenge goes from strength to strength to strength. More than 240,000 of Goodreads' 25 million members have already committed to reading more than 14m books this year, pledging to get through them at an average of more than a book a week. And many fans of books will say hurrah for that. I reckon I'm pretty much in favour of books and literature, too, but the Goodreads Reading Challenge just sets my teeth on edge.

It starts right there in the name. Since when was reading any kind of challenge? Isn't it supposed to be fun? Maybe not for children still learning to differentiate their Perfect Peters from their Horrid Henrys, or for the one in six UK adults who still struggle with literacy, but Goodreads is a site for people who are already "readers" . I don't think they have schoolchildren in mind when they suggest you should "raise your reading ambitions" and it certainly doesn't look like a scheme designed to help adult learners "make it to the final chapter". All this talk of pledging, of targets, of tracking your progress, is just another step in the marketisation of the reading experience, another stage in the commodification of literary culture.

We know that literacy correlates with better social outcomes, that literary fiction can improve our understanding of others, but despite the best efforts of the boffins, literature is one of the few areas of modern life where it's not all about the numbers. Of course figures matter to bookshops, publishers, writers and even libraries, but if we enjoy reading – if reading is in some sense good – it doesn't make any sense for the reader to say that if you double the number of books you manage to get through in a year, it will be worth twice as much.

The strange, collaborative process which happens when you sit down in front of the page, that old magic which forges an intimate connection with the thoughts of someone someplace else is all the more valuable in this frenetic age. Surrounded by information, advertising and commercial opportunities of every stripe as we are, this immersion in another world becomes all the more vital to defend. But whether you're grappling with the effects of immigration, or investigating a safe deposit box left on the Moon, it's not the quantity that matters, it's the quality – the depth of engagement.

The tickbox, cross-it-off-the-list mindset of the Goodreads Reading Challenge points right in the other direction. I'm all for books, for writers and for literary discussion, but if books become just another form of bookkeeping, if we start notching them off on the wall of our literary cell, we may find our "reads" aren't so "good" after all.