is there a real reason we aren't using MMR to decide "rank"

I mean. the promotion series system has to go. its a time sink that exists for no reason. we need to hit a rank when MMR is SHOWING of that rank. that makes sense doesn't it. I'd like a logical argument against that.

so because of an 1/9 jungler. 9 or so hours of my life are down the drain and I have to play all those games again to get to my series and play the series all over again. this is torture.

the dude literally said " I don't feel like playing anymore" continued to walk down mid top and bot and dying. after giving first blood to my mid laner that I was ahead on cs on.

I normally would just swipe it under the rug. but 8 hours of my fucking life are down the drain because of 1 game that was inhumanely impossible to win because of an int feeder.