Because a project that gets one rating that happens to be a perfect score shouldn’t mean it’s the best game in the jam. Statistically speaking, you can say that the more ratings something has, the more accurate the rating is. Something with very few ratings is likely to be significantly off from what it would have gotten had everyone in the jam had the opportunity to rate it.
I’m guessing it’s in there to stop a game that has only 1-2 votes winning over others with many times more votes, but does that happen often?
Yes, it would pretty much happen in most jams since it’s common for people to ignore projects that they don’t think look good. It would be very upsetting to people who put in a lot of effort into their projects to get beaten by an ignored project that got 1 vote.
Another advantage of penalizing projects with very few ratings is that it encourages people to want to get more ratings, and the best way to do that is rating other people’s projects and leaving a comment. It helps build a better jam community.
The rating system skew on itch.io works by looking at the medium number of ratings for the entire jam, so it adjusts itself to how much people are rating in the jam, and doesn’t get skewed by a minority of projects that get a large number of ratings.
Particularly for smaller jams
I’m not sure how small you’re talking about, but if the entire jam only has a few ratings in total then at that point the final results are probably not valid in any case.
Hope that explains.