Why is matchmaking so bad in league?

When you encounter imbalanced games of League, we generally chalk it down to three major culprits: snowballing, matchmaking uncertainty, and/or perception. On top of this, there could be personal factors that matchmaking cant see—lack of sleep, one too many Graggy Ices, that sorta thing.

Does win rate matter lol?

Win rates dont matter in the sense that you shouldnt place too much stock in them. For example a champion with a low playrate but a high winrate isnt necessarily better than a champion with a high playrate and low winrate, and vice versa. It also depends on what elo youre playing at.