One of the best ways of finding something new and tempting to read is by browsing.
Yet one of the biggest barriers to finding what you want is the sheer number of choices that exist. If you walk into a library, you see crowded ranks of spine-on books disappearing into infinity. It's a confusing and exhausting prospect for the browser who has nothing specific in mind.
If you find it difficult to believe that offering less choice can be helpful to readers, just think about car parking for a minute. What happens when you drive into an empty car park? You can't make up your mind where to park, often you park in one place and then change your mind - this side, no, over there - before settling. Compare that to driving into a busy car park - you see a space and you're straight in there, no messing. Less choice makes the choosing easy.
It's just the same with books. Offer browsers a small, varied range of choices displayed face-on. Keep the space prominent, keep it changing and watch the issues go up. And, of course, when the issues go up, you have more space to house more books. Creating small, manageable choices for impulse readers allows you to fit more stock in the whole library and offer more choice for everyone.