I don't want to make this post about all the reasons why I reject something because I feel like I've done that before. Instead, I want to talk about the ways how writers screw up plans and get me to read their entire story which is the only way I'll consider giving it a bump.
...the bar to impress us is much higher than a casual reader who might only pick up a book if it becomes as big as Twilight or Harry Potter. When an editor sees a manuscript in the slush pile, we are not looking to be entertained. We are looking for a reason to reject.