Believe it or not...
Ragequitters aren't getting punished frequently anymore.
Why? Cos most games end 20-25 mins when it's 4v5 and if the person Ragequits at say 15-17 mins, they don't get punished. I've witnessed this twice. Got paired with the same guy in ranked twice in a row. One time he was on my team the other time he was on the enemy team. He ragequit at the 15-17 mins mark and thanks to the snowbally meta of LoL, they won on when he was on our team and they surrendered when he was on the enemy team. I added the guy after and guess what? He had already jumped into another game without entering lower priority queue. This sucks Riot.