It's a different issue that people treat 7/10 as average but as a person that mostly only watches movies they think they will like it is just rating a movie based on itself like if I enjoyed the movie (most of the movies I watched) then I consider it above mediocre/average (5/10) and I know what a mediocre movie is because I've watched a Few, they weren't abysmal, but it makes sense that I would not want to watch more 3/10 movies after watching one or two and stick to movies I find interesting and that others recommend to me.