Although the writer themselves may have completely nothing to do with the style of a book's front cover, they are an essential part of it.

When we purchase a book it becomes something very very personal to us. It can often be strange seeing a book you like with a different book cover, merely because it is not your book. This personalisation, and certainly ownership, of books was at a totally various level at the dawn of the age of printing, with book covers being developed by the owners themselves, and what they believed would be the best books covers for the book. They would buy the book itself from the printer wrapped in paper, then take it to a binder who would bring in the covers to the customer's specifications. This normally meant being clad in leather and then etched with the name of the book, and, usually, the name of the book's owner. People like the co-founder of the impact investor with a stake in World of Books can probably appreciate the ownership that people come to feel in regards to their books.
When you truly think of it, it is rather fantastic that a book's cover, no matter how beautiful it is, manages to stand so eloquently for something that is practically the complete antithesis of its art format-- writing in white and black. In fact, book covers have actually been created to show the vibe of a book and appeal to its intended audience since the dawn of large scale publishing in the Victorian Era. Artists were charged with discovering what makes a good book cover for specific people, or simply put, marketing. Individuals like the CEO of the asset manager that has a stake in Amazon can most likely value the function of marketing in developing book covers.
We like checking out books since they are extremely stunning things. This holds true, but the nature of beauty that we may be speaking about is certainly different to what we might be talking about if we were talking about, say, the visual arts. Or is it? For as long as we have had books we have actually embellished them with beautiful book cover designs that effort to mirror the appeal of what is within. This dates back for as long as the codex itself has been around, with medieval monks, those charged with the protection and duplication of the rare texts that could still be discovered, ornamenting each hand composed text with amazingly rich and gorgeous designs. In fact, such was the beauty held within these books that many of these creative book cover designs were carved into ivory or solid gold, studded with gems, and inlaid with rivers of precious metals. People like the co-CEO of the hedge fund that owns Waterstones can probably value the manner in which the beauty of these book covers was developed to match the beauty within the book.