This post has been up for a while, but I just now saw it so I want to give it a shout out. It's a post over on The Adventurous Writer blog talking about 17 Reasons Why Book Manuscripts Are Rejected. The answers come from agents and editors alike.
It's a very good post. I have pasted a few reasons below. Too see them all, visit The AW blog.
3. The manuscript is too complicated. “If there are too many characters and I have to make a list to keep them straight, then I’ll put the book down,” says Hallie Ephron. Your manuscript will be rejected if it doesn’t flow or transition easily.
7. The writer includes too many stock characters. Beautiful blonde bombshells, evil billionaires, and hookers with a heart of gold are all stock characters - and agent Janet Reid is tired of them! Limp descriptions are also boring. “I want complex, nuanced characters,” she says.
14. The writer has an unpleasant tone and attitude. Reid says she gets a lot of queries from writers who don’t like agents, and those writers are often open about their dislike. She suggests not revealing that you dislike agents.