My first thought was - the rating system itself creates a ceiling to the accuracy of the prediction. And it seems that every one knows that. (Netflix or the 30,

My first thought was - the rating system itself creates a ceiling to the accuracy of the prediction. And it seems that every one knows that. (Netflix or the 30,000 hackers.) Then why spend so much resource to improve 10% of the existing rating system instead of experiment with new kinds of rating system. (I'm sure someone can come up with something clever yet simple.) Yes it's costly to change the infrastructure. But if you don't do it, some startup will come out and beat them to it. The worst part is that Netflix is paying people to think inside-of-the-box (the rating system). I read about Bertoni a while ago and was inspired by his out-of-the-box approach (Behavioral Economics). Wouldn't that give Netflix a hint - "Yo Netflix, here's this dude who's getting the fastest-growing result by extracting more qualitative information out of the quantitative rating system. Maybe you should just design a new rating system that better orgnizes these qualitative information? Just Maybe." Or maybe I'm missing the point here?