Personally, I don't think it matters how I feel about my covers; it's more about how my covers lures readers in.
In the writing world - fiction or non-fiction - covers help readers decide if they want to read the book.
When I'm working on a cover, I ask myself "What does this tell the reader in relation to my title and blurb?"
If you are writing YA, it helps to have the YA character on the cover or some flashy design. So how I feel about the cover is irrelevant. In the end, it's the readers that matter. Well, to me anyway =)