On average, every time I lose n games, I win the next n games (and viceversa).
Basically I entered a stage when I lose/win one match I know i will be roughly win/lose the next n-1 games depending if the last series of n games was a loss/win streak respectively.
Of course there are some outlier games, where one team throws hard even with a large advantage, or when a player (potentially smurf) would solo carry the game. Still, I reached 10k hours in dota and this is the first time I'm tempted to not play anymore this game for good.
I don't want to win because I get better teammates than opposite team, or lose because I have worse teammates. I want to play games where every single game has the same chance to win or lose, and I feel matchmaker has a fundamental role in this.
The pattern is so obvious that if you see recent games you can notice blocks of green/red and everytime I went on a winstreak I got godtier teammates, and the opposite happens when I was on a loss streak. The difference between those series of games is so substantial that you can see from min -1 if game is going to be a loss or a win just by seeing the behaviour of the team at the pick phase, including the picks they do.
It has indeed happened that sometimes the pattern felt like it was not respected, but only to find out that the games I won/lost more than predicted would catch up after 20 games roughly. So yeah, same mmr for more than 3 years.
I climbed from 2k to 4k long time ago with no problems, now every single match feels like it's fixed and I'm having enough of this.
You may say I reached a plateau. It might be, of course, but if matches had a 50% probability to be a win or a loss (and not a fixed value decided by the matchmaking in order to make you reach a 50% winrate in a set amount of games) this would not be possible with such precision. I mean, just look at the image. And this is a portion of a sample size that is 200 times bigger than the one shown.
This pattern tricks me everytime I make a pause from the game too: say I did not play for a long time and I start win some games, i feel more comfortable play more and more games, until i reach a loss streak and I realize I've been tricked another time.
Source: https://www.reddit.com/r/DotA2/comments/p2gmsl/for_the_past_3_years_ive_been_stuck_on_the_same/