How often do you get ''loss prevented''? Does it even exist anymore?

You can disregard the rambling below. Title says it all.

There are plenty of complaints about people losing matches because somebody fed, afked, or disconnected.

I remember sometime last year I was in a Normal / Aram match and if I recall correctly; one of our team mates was missing. We lost the match of course, but when I checked the stats screen / match history - it said loss prevented.

I only do Twisted Treeline intermediates and the occasional Aram now, so I doubt I could run into it often, but I remembered an Aram match I had a few months back where 2 of my team mates disconnected around the same time, and another one of my team members got demotivated and left the game. It was a 2v5, but we didn't get loss prevented.