How does the rating system work? How does it place each game?

Same doubt here

I think it will be the same as in the other game jams.

Each game will be ranked in five categories. After rating time ends up your game will be placed in a particular place in each category, depending on your average rating. So, for example, your game could end up 33th in Overall, 3th in Gameplay, 1th in Audio, 100th in Creativity...

There will be 5 different lists, and you will be able to see how well your game did in each of these categories.

What is stopping someone from rating a game one star on everything?