Matchmaking is just straight up broken, unfair and unfun.
Its no secret that matchmaking causes 90% of the frustration that this game causes. Sometimes you get a jungler who somehow manages to go 13/2/5 and carry the early game and others you get a 0/9/2 Garen top lane who lost both his towers within 6 mins of the game. The ranges of this is just stupid. Its understandable for someone to have a "bad" or "good" game, however I feel like the matchmaking system "rigs" the game before it even begins. This has been going on like this for years and its toxic in its design. This toxic design is the reason that players do not want to play the game anymore, myself included. The only reason people stick around is because they are addicted to the heart of this game.