So, how exactly is this matchmaking balanced?

So, i've yet again hit plat 4, had a decent games, then got a bit of a worse games and ended up with 5 games lose streak. The very next game, howerver, was a bit unusuall. There wasnt a single lane going even. Our team was just getting stomped on and absolutely destroyed. So, logically, I checked to see what's up. (see link) I see that Jayce and Kata are a premade with a really good winrate together, they simply didnt have a good game. That happens. BUT Lee played his 6th ranked in a long time. He doesnt even reach 50% winrate recently. He was not duo with anyone. Just your everyday Gold 4 player IN A PLAT 4 ELO. And obviously he didnt play as good as enemy jungler whatsoever. He couldnt gank a lane, so it was basically a 4 v 5 game without the possibilty of a remake. How did player like this Lee get into a game with Plat4 elo. All of his games seem to be out of his leage. What did he do to deserve this, and what did me and rest of my team do to deserve him?
Report as:
Offensive Spam Harassment Incorrect Board