Fix the matchmaking system

I know I can't be the only person with this problem, you do well in a lot of games and win game after game after game, and then suddenly it's like you're in bronze 5, (yes I am bronze) but just the decisions of your team and the way they play the game makes you question why you even play this game anymore, but you can't leave, you can't just uninstall because you love the game. I don't understand why this happens but you can win as many games as you want it doesn't matter because you can still be matched with people who have the worst match history you've ever seen. No matter who you play or what you do changes the out come of the game if your team mates have no idea what they're doing, i've been playing since late s3 but didn't do ranked until s4 got into b1 tried to make it to silver so many times but yet never could, and then this season comes around and I do my best in my provisionals do better then last season and get placed b5 after getting placed b1 previous, I seriously don't understand how this can happen, why not bring in a mmr system that updates every game, you do well it goes up, you do bad it goes down, you can't have a system that doesn't change based off game to game, it just makes no sense, look at other games out there, hell take cs:go every game you either get bumped up or bumped down, do a ranking system that makes sense and doesn't make people hate doing ranked. Rito pls fix.