Probably there could be many factual or historical mistakes in the books I read that I would not recognize as being mistakes.
I do remember in one of Patricia Cornwell's Kay Scarpetta books, there is a word she used a couple-few times that is NOT a word. I googled it and saw other people were also a little "miffed" at the usage, though now I cannot recall what the word was. I know she likes to use the word "ironical", where i never, ever hear anyone use that word in daily life, even though it is a word.
What will distract me in books is a word I don't find typical, and it can be so silly, like I said before when Dean Koontz nearly always has the word "fronds" in a book but I never hear / read the word unless it's one of his books (maybe I live a from fronds sheltered life),or a narrator mispronouncing a word or pronouncing it properly but not the way we say it 'round here
That kind of thing will send me off contemplating and I'll have to re-wind the book to hear again what I missed while I was thinking about nothing that really matters as far as the story is concerned.
Another thing, maybe related (?) isn't mistakes but things I wonder "
is that really true" or "
does that kind of thing really happen", and I have to do an internet search to learn more! So far, the authors have been correct so I guess even in my light weight book endindulgence have learned a thing or two
When I happen to recognize a grammatical error, it only "bothers" me if it's through the narrator, vs. a character speaking (as they could use improper grammar and it not really be a mistake -- lots of real life people do so, even some of us, including me no doubt!... as I wonder if I should have typed "... including myself no doubt").