When It's Not the Writing
Often, rejections may be so vague that the reasons your work had been returned aren't even clear. It will be up to you to read between the lines. Being creative people, many writers start inventing all sorts of problems. “I can't plot.” “I'm terrible at characterization.” Or even, “I shouldn't be allowed to write a grocery list.” Before you start tearing yourself apart, remember there are many reasons a manuscript could have been rejected that have nothing to do with your skills as a writer.
It might not be your writing. It could be your marketing.
While most writers only want to write, to create wonderful stories, if you don't have an agent, you will need to hone your skills as a market specialist.
If you've received a rejection or several rejections from the same or similar publishing houses stating,
Make sure the type of book you are submitting fits the publisher's requirements. For example, if you are writing historicals, make sure that this publisher buys manuscripts in your time period.
If you read your personal rejections carefully, you may learn which editors seem to like your voice and the type of plots you write. You will also be able to tell which editors aren't so crazy about your voice. Once you find an editor who likes your style, don't hesitate to submit your next book to her. Finding an editor who likes your writing voice is half the battle of getting published.
Never throw away your rejection letters. Not only will you want to refer back to them to see what an editor said about your writing, you will need them for the IRS, to prove you are pursuing writing as a business and not a hobby.
Many writers have been rejected numerous times by the same editor before selling. The writer continued to submit to that particular editor because of the positive comments on prior works.
Editors will often point out if your writing voice, style, or the particular focus of this story doesn't fall into the genre you are targeting. For example an editor may write:
However if too many rejections come back pointing out the lack of tone or style needed for that particular genre, perhaps you should consider writing in a different genre.

