We’re always trying to put you in fair matches that we think you have a 50% chance to win, and do it quickly so you’re playing Overwatch instead of staring at a queue timer. We never intentionally seek to put you in an unfair one.
I’ve seen comments like “I just won three games in a row, so the matchmaker put me in a bad stomp to get back to a 50% win rate”. It doesn’t do anything like that at all. It just keeps on trying to find fair matches. If you do win more than you lose, your SR will slowly go up. As that happens it’ll also put you up stronger opponents that match your new SR. That’s not so you lose, it’s to keep your matches fair.
At no point in MMR calculations do we look at your win/loss ratio and win/loss ratio is never used to determine who to match you with or against. We are not trying to drive your win/loss percentage toward a certain number (although the fact that so many people are at 50% win rates makes us extremely happy). All the system does when it comes to matching on skill is attempt to match you with people of a similar number.
That being said, I don’t think they anticipated that players would interpret the entire idea of “fair matches” to mean “intentionally placing good players with bad players to balance teams out” like you claim.
So please refer to the Popular Myths section of Kaawumba’s topic. It in particular addresses everything you’ve ever claimed and why everything you have ever thought is wrong.