Unbalanced game!!!

Riot i would love to have a good explanation on why NO MATTER WHAT!!!! 1 person CANNOT win the game by carrying so hard all game and trying with everything you have. But 1 person can lose you the game. This game is so unbalanced and it needs to change. Stop adding new Champs and Game modes and actually focus on what needs to be done with the game. Im tired of it seriously. All you guys wanna do is focus on adding new content when you arent even focused on why you are losing most of your top played gamers, and losing more and more community everyday week. Just please focus on what needs to be done.