League of Legends and the Elo system
While I can't deny the Elo rating system an exceptional rating system, I believe there are inherent flaws when it is adapted into use for team-based games.
The Elo system was designed for use in 1 vs 1 style games and values only the win or loss. And yes, I can see how this can work on team-based games such as football and baseball. It is my belief, however, that this system in fact fails to work for League of Legends effectively, primarily in the Solo Queue ranked.
It is not uncommon that players end up in a lower rating than they truly belong solely because of poor players on the team that throw the game dragging the team down.
All too often one or two players on a team will be a controlling and dominate factor, but will be on the losing side because the rest of the team will not play safe, smart, or tactically. They will play too aggressive in their lane, causing the other team's jungler to take a focus to them, and after being ganked once or twice they still play aggressive, repeating the whole process to infinity. The common result of this isn't them taking a look at their own personal game-play and trying to improve, but rather they tend to blame the rest of the team.
Is it fair to punish the teammates that play well for the ones that don't? While we all have our bad games, our bad days, but the one things that will always show our usual potential on the long term is our KDA. While changing the Elo system to something new to better rate players according to them personally and eliminate the effects of being "carried" and "drowned" is not entirely the easiest thing in the world. It is not the hardest thing either. I can honestly have one flushed out in a week.