Well, of course you can! There's no guarantee that your judgement will be accurate, but we judge books by their covers all the time. The overall look of the cover can tell you a lot about the book. Where (and when) is it set,? What it is about? Does it fall into a specific genre?
In some romance sub-genres (historical, paranormal, and science fiction) there's a real trend to put a man's naked torso on the cover. The man's head might not even be visible but his abs certainty are. This is a signal to the reader, It says "This book contains hot sex scenes." It works well as a signal, but of course, it doesn't distinguish one such book from another.
Recently, a post on Lit Hub had fun with the concept by taking classic novels and creating pulp-style covers for them. Some of them aren't all that different (although I doubt there was a shirtless guy on the original Great Gatsby cover), but some are amusingly pulpy. I loved the Madam Bovary one. Moll Flanders, on the other hand, looked like a cover the author might have selected.
So, with that in mind, how does the cover for my upcoming book Alien Vows (sequel to Alien Bonds) strike you? This is an animated version, obviously, but except or the stars turning, it's what the ebook will look like. You will notice the guy is hot but he has his his clothes on. I don't want anyone to be disappointed and I don't write steamy; it's all happening in the book, but it's not in detail on the page.