This is the philosophy that I apply to my review scores, whether I am reviewing a movie, a game, or anything else.
I’ve found that most reviews seem to assume that every piece of art should be a 10/10, and then deduct points for anything that the reviewer didn’t like. I think that this is a fundamentally flawed approach, and every bit as much of an issue as starting the scale at 0/10 as a default.
I consider a 5/10 to be the default. A 5/10 is what a movie/game gets simply for existing, and anything that it does well moves it up the scale, whereas anything it does poorly moves it down. The most mediocre film/game on the planet would get a 5/10, one that is generic and standard, but provides at least some level of enjoyment would receive a 6/10, and so on. A 0/10 is something that has absolutely no redeeming qualities and is a complete and total waste of time. A 10/10 is something that is flawless. I have never awarded a film or game a 10/10, because I have never seen a genuinely perfect movie, nor have I played a game without even a single flaw. I live in hope though.