How Can Someone Who Feeds Every Game Climb?

Recently I queued into a player in a Gold match, he was our jungler. He was god awful. He didn't even have the mechanics to fully clear his jungle without having to back early on and he struggled to even clear his jungle the entire game. Needless to say, he didn't gank any lane the whole game. He ended up feeding the enemy jungler terribly after they apparently realized how unskilled our jungler was.

I was curious as to what was going on, so I decided to check this player out.. He does poorly literally every single game. I checked his match history back a long ways and he's only a handful of games in the hundred games I looked at where he did pretty decently. The rest of his games were like "meh" or really bad.

I really don't understand.. how does a player like this manage to climb?!

Carries no games, feeds every game. He does nothing for his team (judging by his match history) yet he has managed to make it not only past bronze, but all the way to gold.

This has to be the most mind boggling thing I've probably ever seen.

[slayer-jinx-unamused]