A: I don't know, but I'll know it when I see it!
This pic has some of the books that came across my Goodreads feed this week. I usually get 500+ recommendations from friends reading lists every week. There is no way I can look at all of them, so I do what most readers do--check out the cover. These covers did their job and made me go to Amazon and look them up to see if I wanted to buy them!
Here are some of the thoughts I've been kicking around about what makes a great cover:
•Draws attention and generates excitement, holds the eye
•Represents the genre
•Blends all elements to create the right tone and balance
•Portrays life and/or movement
•Is uncluttered—Less is more (blank space is good)