I feel like the score rating system is bugged.
To anyone who cares, the title says my feelings. I have had a few games that I have seen people play wonderfully, but end up with a low ratting. My prime example is a game I just finished as Janna. I wen 1/5/62 and only scored a B+. If this were the first time I had seen this happen I wouldn't complain here on the forums, but I have seen/heard this happen way too frequently.
I had managed to survive against a brutal team of heavy burst and insane CC for 38 minutes with only 5 deaths, assisted in almost every kill for my team, and push my team to victory in a 4V5 situation that looked helpless with a first time Tryndamere.
http://i132.photobucket.com/albums/q11/yankotsu/CHEATED_zpsamqs3ocq.png