Yes, ESPECIALLY on this forum where, by the time you notice that you posted a "typo" (despite proofreading your message), it is almost too late to beat the short 5-minute cutoff allotted for any corrections.
I'm normally a birddog on spelling and grammar, but this one forum has taught me to just ignore most of it because I know the posters don't have much of a chance to rectify anything. I have permanent mistakes standing forever, here, that I would never leave on a forum with a reasonable correction time given.