1. You queried a novel that is the second in a series, and you self-pubbed the first. It's almost impossible to sell a second novel in a series even if the first one was published by a major house. And self-pubbed is almost always a non-starter cause of the sales figures. Publishers just aren't interested in a book that sold 600 copies, unless it won some sort of prestigious award, or got optioned for a movie, or some other reason that persuades them more copies will fly off the shelves.
How you will avoid this: write something new, or treat book two as the first in the series. It will also help if you remove it from Amazon before querying.
2. Your memoir is a retelling of Eat Pray Love. You even use it as a comp.
How you will avoid this: If you want to write this kind of memoir, you're going to need to talk about it in a way that makes me think you've got something new to say. And "new to say" doesn't mean "it's about ME, not someone else."
3. The title indicates your values are so out of sync with mine that I don't even read the query. (Example: Only Sluts Get Abortions; Gays are Evil; Immigrants are Terrorists) I respond poorly to these kinds of hot-button-pushing projects in general.
How you will avoid this: if you want to write a book that takes a position on a issue, frame your argument in something less incendiary than good versus evil. And remember that most people won 't shell out money for a book if the title just makes them mad.
4. You self pubbed the book you're querying me for. Other agents consider them. I don't.
How you'll avoid this: Either don't self-publish, or just leave me off your query list.
5. Ho-hum. The plot of the book is so run of the mill that even good writing can't save it.
How you will avoid this: know your category. If you don't know what's already been done, and done to death, it's hard to know what's fresh and new.
6. You describe how characters look but not how they are. I'm less interested in eye color than I am in moral compass. One is filler. The other isn't. If you don't know which is which, stop querying.
How you will avoid this: learn to read your own work with a critical eye. Make a list of the adjectives and adverbs you use to develop character. If they're all external (big, strong, tall, glamourous, sexy) or patronizing (spunky, feisty, Mr. Mom) you've got a problem.