Occasionally, it is the case that misprints are annoying enough that you forgive the person who has taken the trouble to point out the correction in spite of it being fairly obvious in the first place.
Other times, that person has not only defaced the book but got it wrong. Or at least not improved it. My recent examples:
“The situation, however, is even worse than Saussure describes it.”
“The situation, however, is even worse than what Saussure describes.”
“Once upon a most early time was a Neolithic man.”
“Once upon a most early time there was a Neolithic man.”
Do these people just not get it?