The you're addressing here is The four-point scale, which exists primarily because rating a low score on a big developer's game is a good way to ensure you don't receive review copies ahead of release, something reviewers live and die on because their fans want to know ahead of time whether the game is any good. In that sense, it's a bit of a paradox - you can't be sure at face value whether the 4 out of 5/8 out of 10/83% was something that the reviewer genuinely levied against the game as a fair criticism of flaws and/or commendation of positive experiences, or if they give it a high number because they're afraid of biting the hand that feeds.