I like to correct people on mistakes in their books I'm only trying to help everyone if they want to publish their works or anything properly. Also it makes their work look better when it is more grammatically correct.. Their punctuation is right.. Words make sense sentenses are correct words are spelt right. I'd want the same too if any of my works had mistakes im trying to help not put people down, make them look stupid, be rude or anything they will lose readers if it's hard to read or it doesn't make sense I certainly have stopped reading plenty books with mistakes in.. You don't see professionally published books with mistakes in (I did once but..) i know these books aren't professionally published yet but some of them could be with hard work and help.