I'm currently Silver III. What do if you have someone on your team that literally goes in 1v5 every other minute, has no concept of positioning, and does not listen?
What do if your team chases that last kill for 45 seconds after winning a teamfight instead of pushing an objective?
What do if you get that one person that has 8 CS at 20 minutes and is 0/9?
I've had all of this and more, in roughly 20 of my last 25 ranked games...
What do?
I focus on getting better myself, I focus on getting better CS, I try to determine when I should roam etc. Yet, as soon as I hit Silver II, completely incompetent teammates (usually just that one guy the [expletive]s it for everyone...
Great example: I was jungling, I went to gank toplane (who was struggling a tad (GP vs I want to say Darius? i don't even remember)) and we get the enemy laner low enough that they HAD to back. There was a MASSIVE minion wave about to push down on his turret, so I took three minions as a tax for giving him what is essentially 30+ seconds of absolute free-farm. As soon as I took the third minion and left his lane, GP went up and executed on the enemy turret...
So I went back and started last hitting the minion wave so it would be in a favourable position for my next gank (pretty close to our turret), and he starts pinging me to back off and cursing me out in chat...
What do?