#1 with a bullet to the back of the head: “ebook sales declining”.
Maybe charging 16% more for the Kindle edition than they do for the hardcover has something to do with it? Note that the paperback edition is no longer in print.
I don’t remember what specific book this was. It doesn’t matter, because when the publishers set the price, the Kindle edition is almost always more expensive than the paperback, and pricing it above the hardcover isn’t rare.
And if you look at the reviews, the Kindle editions from major publishers are frequently riddled with errors, and illustrations are often misplaced, mangled, or just plain missing.