There are many trends when it comes to young adult book covers--girls in dresses, large eyes on covers, putting only part of a person on covers. One of the possibly lesser-known trends is duplicate covers. Some people call it cover couples: when one cover of a book is identical, or nearly identical, to the cover of another book. Here are some examples.
North of Beautiful by Justina Chen Headley
Evermore by Alyson Noël
Taurus Eyes by Bonnie Hearn Hill
After Midnight by Lynn Viehl
The Iron Witch by Karen Mahoney
So Much It Hurts by Monique Polak
The above books are a small sampling of duplicate book covers. Even when the cover designers crop the images, add details, change the colors, or flip the images, it's still pretty obvious when a cover image has been duplicated.
The trend isn't just limited to young adult novels, either. Some young adult books have the same covers as adult fiction books, and plenty of adult novels have the same covers. Sometimes, there are more than two books with the same cover image, as well. Here's an example that combines duplicate young adult and adult fiction covers and more than two books with the same cover.
You Have Seven Messages by Stewart Lewis
The Miracle Girls by Anne Dayton (not in the library catalog)
These Girls by Sarah Pekkanen
Some people would prefer books to have individual covers as this post indicates. For others, it might not matter. Even authors are weighing in on the topic. Author Marissa Monteilh, a contributor to the blog Novel Spaces, discussed her preferences about duplicate book covers last month.
I haven't decided yet how I think authors and publishers should approach this trend. It's easier and less-expensive to use stock photos for book covers, as many do, but I'm not always a fan of seeing the same cover on more than one book.
For a more in-depth list of books that have the same covers, check out this Goodreads list.