I usually know the difference between right and wrong. I have often criticized, or at least sneered with disdain, at people making grammatical or spelling mistakes, like treating data as a singular noun or writing "capital" when "Capitol" is called for.
But I've grown sloppy or lazy over time. It has been ages since I went through the multiple keystrokes to put the accents and umlauts and other such marks on foreign words imported into English. Thank goodness for the copy editor on my forthcoming book for insisting on -- and adding -- the appropriate marks.
Thank goodness also for The New Yorker and its astute copy editors who insist on using the diaeresis.
Someday I'll tell you about their extraordinary fact-checkers.