I have just gathered data for 100 games, my overall average WIN CHANCE was exactly 39%. In practice, that means you lose at least 2/3 of games, no matter what you do.
Horrible, unbalanced and UNFAIR match making win chance is the reason I uninstalled. I think only noobs and new players are playing WOT because they are completely unaware how terrible this game is. And a portion of MM privileged players who think they play very good, but in fact they play against very low skilled teams, not much more intelligent than bots. In WOT you don't lose or win, it's MM win chance that decides if you lose or win. You don't have a lot of chance to win when almost every game starts with your team losing 0:3.
Huge gaps in MM win chances mean that your contributions as a team member of 15 players are completely irrelevant.
If you constantly get bad teams, gather data of your average win chance for a large number of battles and you will see. It's all about statistics – which in WOT for many players are horrible, making the game literally unplayable.
Source: https://www.reddit.com/r/WorldofTanks/comments/cro873/stop_playing_world_of_tanks/
