Reddit reviews The Monogram Murders: A New Hercule Poirot Mystery

You don't have to write well to be published. You have to write what editors think can sell and poorly written 'well plotted' mysteries sell like hotcakes. After you put out a few books that sell well, publishers get indulgent, which probably explains the poetry.

The Amazon excerpt from the book they mention in the article is as dreadful as I'd expect from someone with Dr. Seuss and Mother Goose as her touchstones.