Mistakes are mine, all mine. In the second edition of my self-published book I have included that phrase. An acknowledgement that my beta readers and editors are not to blame for faults readers find.
To be honest, I do not always accept an editors suggestion. The spectre of the traditional publisher rejecting work because the writer failed to comply with suggested edits does not exist with self-publishing. I read a lot of books, and many self-published books are riddled with plot errors, grammar mistakes, and typos.
What mistakes do I mean? Anything that detracts from the ‘dream’. My editors may not like a word I used or think it is not the right word to use; or the syntax is at fault; or a metaphor doesn’t work for them. I give their point of view due regard but decide whether to change things or leave them as they are. If I leave things as they are, and readers think they are faults then the mistakes are mine, all mine. If editors are named it is unfair of me to allow readers to think they failed in their job. With that in mind, I now include that statement in my acknowledgements.
Hiring professional editors is expensive but worthwhile, if you can afford it. Other options include members of a writing group, friends and colleagues, or joining an online resource.
One such resource is www.scribophile.com. It may not be as much about editing but members critique work posted on the site. After they earn sufficient points can post their own work. It allows authors to post short stories, poems, novels and anything in between. Plus the author states the word count (up to 3,000 each time), the genre and the sub-genre e.g. novel, literary, fantasy, adult, so a reader can choose favourite genres or try reading something new. Readers can give a general critique or go through the work making comments on plot development, characters, grammar or any mistakes.
The site is a community of like-minded people. Groups can be formed, forums on a variety of topics accessed as can the page of contests and the blog. Lots of helpful information for writers of all levels.
There are many more such sites out there. If you know of any, send me a comment.