I grabbed the previous statement from this article, but you can find countless similar passages online. Most of them have a congratulatory angle about how "You msut be a gneuis if yuor'e albe to udnretsnad tihs srcamelbd txet."
But you're not a genius. You're doomed.
Because when your brain automatically makes incorrect words seem correct, then how the heck are you supposed to identify misspellings? And don't say "autocorrect." Autocorrect is a conniving backstabber. If you write, "Libraries serve the pubic good," for example, autocorrect will just whistle nonchalantly and look the other way.
I am a professional copywriter, and a perfectionist by nature. And yet, I overlook spelling errors quite often. Too often. And I hvae olny my gneuis brian to blmae.