Yeah, I was tempted to say 10. It's one of the funniest movies ever.
I wanted the potential user to see that 10's should not be given lightly. I was trying, as much as possible, to get all users on the same "scoring" page. answering: "What's the minimum points a thing would need to score to qualify as 'Good'?" That way, the scores mean something. Maybe they can be compared.
Plus, lot of features in scorethings were inspired by this xkcd joke about star ratings: https://xkcd.com/1098.