I know that behind the reason is to balance out on having better players help out some struggling players or new to the game. Now in theory this sound great that good players helping those struggling in the game. Now in execution this just brings in huge flaws and down right frustration when being group up with bad players (trolls, feeders, int., etc.).
I mean how are we suppose to level up to the next tier when you have 1 bad player and occasional with a struggling player on the team. You are down to at least 3 good or somewhat decent players? If we are going to at least group up with new/struggling players with good/decent players we need a system that filters out who is new/struggling player and who is a bad player to be grouping up with the good/decent players.