I don't usually play ranked. I play normals. Why is it that I am paired with Diamonds, Masters and Plats in normal games and with my fellow silver peeps in ranked?? My normal games winrate is lower than my ranked! i'm not nearly as good as riot's normal matchmaking thinks i am. right now, i play ranked for leisure and normal feels like i have to tryhard not to win, but to not lose embarrassingly. Wtf rito!
Because your MMR for ranked play and normal play are seperate. You have 2 different MMRs. So when you play your ranked game you are matched with people near your ranking.
But when you play a normal game it matches you with people near your normal game MMR. And when you see the load screen and see plat and master tier banners that is their ranked banner showing but for normal games they may have a MMR closer to yours so they are matched with you.
Because Riot's matchmaking is shit. That won't stop the apologists coming out in droves to explain this bullshit away though.
