Many novice writers make the mistake of thinking they do not have to edit their manuscripts before they submit them to a publication, agent or publisher. They have the mistaken idea that editing is not their job because the publisher has someone in-house to edit before the manuscript is published. The reality is that the editor will not review manuscripts that contain numerous errors. When you submit your manuscript to a publisher without taking the time to self-edit you run the risk of finding your hard work going right into the slush pile.
One of the things writers need to remember is that more publishers are reducing the amount of time they allot to editing functions. They depend upon writers to submit manuscripts that are clean and free of errors. The function of editors is not to spell-check and proofread the work of editors but to make sure the document adheres to the guidelines and is in accordance with the approved topic. The editor may also verify the facts and sources of information, but it depends on the publication.
When it comes to fiction, it is very unlikely that editors will do much proofreading, spell checking or grammar checking. They are usually looking for formatting, structure and plot. If something stands out they may fix it, but that is not the purpose of editing fiction. Of course, this is AFTER the manuscript has been approved for publication. On the initial submission they will not be doing anything but looking for plot, structure and potential salability. The editor will overlook a few minor errors; after all, even the best proofreader and editor can miss something. However, the manuscript should be as perfect as you can make it.
If editing is the responsibility of the writer, does that mean each writer needs to invest money into paying a professional editor? While it is a good practice to develop, you can certainly avoid the expense if you have a friend who can objectively review your manuscript. having a second pair of eyes review your writing is always a good idea. Remember, you are too close to the writing and will have a tendency to read what you meant to type rather than what you actually typed. Another way to avoid hiring an editor is to put the piece down for a month or so and then reread it with fresh eyes. Certainly this will not work when you have a specific deadline, but if you are working on a book or short story, it will definitely work and is a good idea. In fact putting your story down for a while will also help you see any flaws in your storyline
The most important thing to remember is never under any circumstances submit any work that is not as perfect as you can make it. Read it, reread it, read it again and have others read it before you send it to a publisher or agent. No matter how good your storyline may be, if you submit it to an agent or publisher with many errors, it will end up in the slush pile. Even worse, you will find your name on the black list with other publishers–remember, they talk to one another, and an author who submits error laden work will make the rounds among editors and publishers.