Covers serve many purposes:
a) It gives the reader a hint of what the book is about;
b) It keeps the content safe from the weather elements ie: rain, snow,
c) Bed covers keep a body warm at night, or during daytime naps
There are good covers, which entice the reader to pick up said book and thumb through it, or flip over to read the back cover or the inside book jacket.
Then there are bad covers, which give absolutely NO hint of what the book is about. And you've all heard the saying, 'Don't judge a book by its cover'? Well if I showed you a plain green cover with 'All She Ever Wanted' or 'Teacher's Pet', would you be tempted to investigate further? (Not discounting author name recognition...but that's another topic altogether!) But if I were to show you two people of the opposite sex; both smiling; he's handing her something....with the title 'All She Ever Wanted', wouldn't you be interested in what it was she wanted? And if he gave it to her?
Likewise, Teacher's Pet. A plain blue cover won't tell you very much. But picture two people kissing and leaning up against a desk or a blackboard in an obvious classroom, and you'd be a little curious, no? At least that's what my cover request said, with some examples from photoshop, or whatever that site was. I hope she's able to 'get' what I was trying to convey.
E-books covers function more in a Promotional capacity. I'll admit, the catchy blurb and excerpt are my main means of putting a certain book on my TBB list. I really don't pay much attention to e-covers as I do the print ones. But to people who like covers and judge the book accordingly, they are a HUGE part of getting the word out, in a visual sense on blogs, websites, and social networking. When I'm on Facebook and post a picture of my cover, people will take notice of it if it is eye-catching. Likewise, a person may click on any links I may post about it.
I've heard it said it takes an average of ten mentions before a potential reader will consider buying an author's work. What makes me put any book on my TBB list? As I've said, the blurb and excerpt. But I've also been guilty of not putting it on the list until I've either read another excerpt more to my liking, or I've developed a friendship with the author and agreed to try out her book. Sometimes I come away kicking myself for not reading it sooner, and some times yeah, my 1st instinct was right. But not everyone has the same taste in books. And I've already admitted mine are eclectic.
That being said, I'll let you know when my latest cover is ready. And if it's less than awesome, please read the blurb and excerpt before making up your mind?