Question on MMR

I've played this game enough to know a decent player from a bad player.(No I'm not going to bring up rank because the system as I see it is broken)

Bad player: plays for kills. Split pushes and dies a lot. Match history will show you that this player is even or negative kd. rarely postive.

Good player: Plays for kills, split pushes, roams, wards, punishes the enemy for roaming, and mechanical skill is ok.

pro player: From what I know have all that plus their mechanical skill is ridiculously good.

Anyway my question is do you base mmr on games won? or the performance of the player? Like does it take into account the vision score?, kill participation? Dmg received vs deal? turrets destroyed and at what times?

There's a difference between a gold player with silver teammates losing to a team with a silver player with gold teammates.

Someone might boost themselves to plat IV, but I doubt they'll do any more ranked games because they simply don't want to lose elo, so they're not going to fuck up other plat players games for the most part.

Now DUO boosting can be a problem, but I don't really want to talk about that.