User blog comment:Leyrann/Placement Matches - The toxic that creates the Elo Hell feeling/@comment-4022742-20121129085639

The KDA system solution is terrible, for tanks and supports would be dependent upon other peoples skills to rise in ELO, if your team ditches you during a perfectly good engage while you were goin 0/0/5 from laning you can easilly end with 1/12/7 just because your carries run and don't respond to pings.

It also doesn't take into account how much you dienied the enemy, warded the map, stole buffs, killed towers and inhibitors. Just a trivial score count that's not an actual objective.