There seems to be some phenomenon where people are always either on a win streak or lose streak.
I constantly meander between ~80% win streaks and ~80% lose streaks. This isn't even in Ranked, which is where most people complain about this happening. It's hard to believe that it is down to chance, considering this is posted about fairly frequently - yet I never see any explanation as to why it occurs.
The fact that it happens in normals too just shows that the matchmaking mechanic seems to exist throughout all PVP matches and is not limited to ranked as some people seem to think.
I don't think my in game performance varies so greatly that it justifies such wild swings in win/loss rate.
It always boils down to whether I get competent players on my team, who understand the concept of teamwork, and are focused, or whether I get the team where the Riven runs past the tank to 1v5 the enemy team whilst our Braum splitpushes bot lane during teamfight.
It is **IMPOSSIBLE** to win with those types of teams: very frustrating when you are trying your best to turn the game around.
You would think this is luck of the draw - but wouldn't the average be closer to 50% in that case, rather than swinging between the extremes?