From Bryan Thomas Schmidt:
At some point or another, all writers have to consider whether or not their manuscript could use an editor. For most pros, that’s not even a question. I’ve used editors on all novels since the beginning and all of them have brought great benefit and growth to me as a writer in improving my work. As I grew, I started editing myself and have been editing freelance since 2009.
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1) Independent Editors are your friends. Our job and living come from helping writers make their work better, the best it can be. It’s the passion that brought us to freelance work and the risks inherent in that, and it’s what keeps us coming back for more. We are not acquisitions editors looking for a reason to say no. We are not motivated by favoritism and we are not out to crush your dreams. We want your work to sparkle, and we’re thankful you’ve given us the opportunity to help.
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4) Independent Editing Takes Focus and Time. Editing is detail oriented. You want someone to read carefully and consider the big picture of the manuscript, not just each page individually, but as a whole. You want the editor’s notes to reflect that. Because it’s difficult to do line and copy edits and developmental edits simultaneously, that means we may need to read your work more than once. That takes time. Because it takes focus, we often can’t edit multiple projects simultaneously. We need to keep our head in the game of your manuscript. So when you’re our current project, all of our focus is on yours. That means, until we’re done editing your work, we aren’t free to work for anyone else. You pay us to make time and do it right. Editing is not where you want to be cheap, folks. Professional editors at publishers get paid very well per hour. Most freelancers make much less. Keep this in mind next time you complain about how expensive independent editing is.
Link to the rest at Brian Thomas Schmidt