Back in the old days of 8bit computing, I remember a few magazines used to explain their scoring system.
Most magazines reviewed a game out of ten. A score of five would be an average. The game is just ok. Not brilliant but not terrible either.
A great game would be an eight or nine. Very rarely would a game receive a ten as that indicates perfection.
In today's world, the way people talk, it feels like a game needs at least an 8 (or 80%) or it's not even worth touching.