I suppose it depends on the one editing. I had an indie publisher that had supposedly edited my work. They didn't even touch it. I would have been better off editing myself. And I probably had more background in grammar and proper English, as that I minored in English in college, than those that were 'editing' my books. Most indie publishers are a joke. Sorry to be so harsh.
Algernon, welcome to AW. I'd appreciate it if you'd read our Newbie Guide (there's a link at the top of the page) and acquaint yourself with our one rule: respect your fellow writer. Many of our members are published with perfectly respectable independent publishers, and quite a few more work for those independent publishers: to dismiss "most" of them as "a joke" is not only inaccurate, but rude.
Thanks.