Here's the thing: if I don't like the cover models, or if I picture them differently in the story from how they appear on the cover, the cover is a disappointment. Which is why I generally don't like full-on faces on book covers. When you write a love story, it's personal. You get inside the heads of your hero and heroine in order to make them seem/feel real to the reader. With that "reality" comes a visual, and if the visual, which of course won't be the same for every reader, defies the reader's idea of what the hero/heroine should look like, the cover subtracts from the overall experience. At least it does for me. And, frankly, this happens more often than not.
The simplicity of this is that each reader's personal tastes in beauty or handsomeness is unique. Sometimes there are those who have a universal appeal. Nearly everyone finds certain women beautiful, sexy, attractive, and certain men handsome, sexy, hunky, etcetera. But, unless an author is writing a story about one of those universal characters, a book cover about fairly ordinary or regular individuals means they can certainly be good looking, pretty, attractive, handsome, cute, and/or sexy, but their images still have to transmit, let's say, less glamour than a celebrated actor with universal appeal.
All of that to say this, authors and of course cover designers take a calculated risk by giving the reader full visuals of their selected models. But, unlike me, I doubt most readers are as sensitive about seeing and equating those cover models to the story they read about inside the book.
What are your feelings about cover models and the stories within the books?
Father, thank you for cover designers. You have given such wonderful talents to all kinds of artists. May each one know from where that incredible talent comes. In the Name of Jesus, Amen.