... typos, grammatical errors and absent-minded apostrophe use in my OWN POSTS. It just goes to show how the brain can let you down. At least one has the opportunity to go back and fix these 'grammar sins' and hope that no-one saw. But sometimes it is too late. Oh calamity.
Such faux pas are deemed even worse when you try to make a living from editing and publishing. Things I often do absent-mindedly in my own writing include inserting the wrong homophone, e.g. elicit OR illicit | new OR knew. I know the right one to use; I am just in a super hurry to get the post written and clearly not paying as much attention as I should.