On boards some players argue that others starts playing better when listening to others flaming them. I just had a game that can be a proof that being quiet or positive leads to better results.
The story of the game. Playing as Tryndamere top vs Garen (ranked). Early game was little on the Garen side, but nothing that I could change the moment that I get my ultimate skill. But just after I hit 6 game decided to kick me out. I was out of the game for some time (not that long, as it still counted as win and I got no leaverbuster) and during this time Garen was not taking a sun bath at river.
When I reconnected I was almost 4 levels behind and around 2 items behind. I tried to lane under my tier 2 turret, but I was destroyed. I was killed, and killed, and killed. Garen was getting more and more fed, and even with a help of jungler he was unkillable. Nightmare.
But the team was quiet, they said not a freaking thing for a whole time. They did not ping me, they even reacted when I asked our jungle politely if I could take his golem camp. Thanks to that I was slowly catching to rest of their team (except of Garen, he was already 18).
Thanks to the fact that I was able to concentrate on doing my best and team was also spending their time to play as best as they can, tides of game has changed. From losing all lanes we came to winning all lanes. And from me being so behind that I was one shooted, to me being useful (to some degree) in team fights.
Tl;dr: being quiet, not complaining about your teammates, helps your teammates more than flaming them.