Have you ever misspoken, only to have someone correct you right away? Are you thankful that the person cared enough to point out your error to everyone within earshot? Some people just can’t resist pointing out other people’s errors, regardless of who’s present and how minuscule the error is.
I once knew someone that would jump at the chance to correct everyone at every chance he could. From grammatical errors to pronunciation mistakes to misspellings in email messages, this guy couldn’t resist adding his two cents and showing everyone how smart he was and how dumb everyone else was. How did people like this person? They hated him.