Editing is a real pain, but a necessary evil. I'm spending countless hours editing Blessing or Curse, my five story romance/science fiction anthology, to get it just right. Even after the best screening, I know a few errors will crop up, because it's almost impossible to produce an absolutely perfect manuscript.
Still, there are limits. When a book is not edited, or done sloppily, it's immediately noticeable. I very recently quit reading two books, which were fortunately free. I won't name titles, because I don't like embarrassing people.
Problem with the first:
Too many coincidences.
I'll go along with one, but when they pile up, the believability factor flies out the window. Fiction isn't real life, yet the author needs to make a good case, so the reader can pretend such an alternate world exists. Yes, truth is stranger than fiction, but such strangeness doesn't wash in a book.
Problem with the second:
Everyone is human and can make mistakes. Even an editor can miss a repetition. I'm not talking about a repetition purposely included for emphasis, but one which seems to harmlessly appear in the flow of words.
When the same phrase appears a few paragraphs down in the same page, that gives me pause, but I'll ignore the redundancy. However, when another phrase gets the same treatment shortly thereafter, I lose patience. It's obvious the book has not been properly edited. Maybe the story is good. Maybe the author can convey emotions and pull at my heartstrings. I'll never know, because I've already removed the book from my Kindle.
What about you? How much patience do you have with sloppy editing? Have you seen any recent examples?