I think Matt did all the necessary explaining here:
https://www.youtube.com/watch?v=FDjac8grplU
I used to love URF only because of how fun I can have regardless of winning or losing. Why? Well because I got to try out how a specific champion would work with a specific weird ass build without having to deal with a Karthus ult every 50 seconds?! Plus, I got to PICK the champions that I wanted and had the CHOICE to avoid the champs I hate, which are quite a few to be honest.
So I just wanted to say Riot ... Please do bring back Draft Pick URF.