That's comparing books by a single publisher in what looks like a very specific series, with paperbacks from different publishers. The former - the one you pre

That's comparing books by a single publisher in what looks like a very specific series, with paperbacks from different publishers. The former - the one you prefer - looks institutional to me, like something a hospital or childcare home would buy in bulk, at a discount, to provide reading material for the unfortunate inmates. The latter has a lot more distinctiveness, and is chaotic since the book designs individually try to grab attention, so that they sell themselves in a bookshop. I don't particularly love the result, it's an artifact of how books have been sold over the past century, but it's preferable to the former by some distance. It's far easier to spot a book whose cover you know in the second style.