Matchmaking

Recently, I spoke with a member from Riot support who said that the matchmaking system takes into account however many wins a summoner has and matches them up with other players with a similar amount of wins. Does this not mean that those with low wins (losers) will play with other low winning players? They say they aren't deliberately setting us up for failure but how can you succeed with other players that suck? sure, some of the players may not be bad but why would you take into account how many wins a summoner has to match them up? This riot member also said that they don't match toxic players up with other toxic players, is this not the same concept as matching players with low wins with other low winning players? Ultimately what decides who we gets match made with us is our MMR, and it only goes up a good amount if you defeat a tough team. How can you defeat a tough team if your matched with players who aren't good at the game? I'm a decent player, I do good in 90% of my games, but due to my teams I lose 70% of my games. I know some of you are going to say its not just about ME doing good in my games, its about helping my team. I help my team out as much as I possibly can but to no avail have I been able to keep them from trolling or feeding. I play nasus a lot (400 stacks 20min, usually) some games I carry and others I get stomped on by the enemy adc who is 15/3. Although you guys might think that I farm the entire game, that's wrong, like I said I help as much as I can, when I can. what do you guys think about the matchmaking system