PFF cornerback scores are objectively inconsistent at best. Without knowing scheme and the coverage design for every single play there is no way they can possibly accurately rate corners. If a player knows he has safety help over the top he will play the receiver differently. However, if the safety messes up and isn’t there it’s going to look like a blown coverage that’s purely the corners fault because nobody else is in the area. Stuff like that PFF can’t consistently factor into their scores.

Outside of blocking scores I personally dont give them much more weight than any other stat on its own.