Poor grammar reflects poorly on the website. We owe it to Mr. Robinson to look our best - or at least try to.
Poor grammar reflects on the person who writes it, not the site nor Mr. Robinson. It does however reflect on a person who has to point out one instance in a paragraph where the difference is either plural or possessive in just one word. It makes it appear they have nothing better to do but to scan posts and correct mistakes people make in either spelling or grammar rather than saying something enlightening. And correcting a mistake someone makes is petty. This is not an English class or exam.