Why is matchmaking so awful in this game?

I have been playing league for a bit and have noticed how utterly awful the matchmaking for this game is. I am low elo (bronze 2) and i have a good winrate but i get put into games with people who constantly afk, feed most of their games, and people who are extremely toxic. Riot games needs to fix this it is an awful problem and makes me want to stop playing the game.