Get your shit together Riot

People from Riot - can you explain me, how the hell a full tank with over 180 resists both kinds and over 3000 hp can die in 2 seconds from two champions? They werent fed too much it was just an even game but still... they could kill me as a tank in 2 seconds being full offensive style and we as a whole team couldnt kill any one of them even using everything on them (5 ults, every single cooldown). Why does your game seem like building only damage is a way to win? Tanks die just because (TBH your ways of counting damage sucks, not to mention the fact that death recap is bugged since season 1 and still nothing was done to fix it) and people with only damage items can survive the same shit that tanks die in without any problems dunnno why and dunno how... can you do something with that bullshit? Or at least explain to me how a champ with only damage items can be more durable than a full tank?