Why I believe Loss Prevention should be Permanently on for certain situations.

I just had a game where my Jungler rage-quit after dying for the 3rd time. My support DC'd for a minute prior to that so our mid decided that the game was just automatically lost and quit. My support Reconnects moments later but we were down 2 teammates. I feel that it's unfair to punish the remaining people with loss of LP because someone has a bad attitude.