Rock, Paper, Scissors
Pretty much always, but especially in the current meta, I feel like tanks are a little too much to handle. I've been late game versus a Volibear and/or Udyr. Doesn't matter how much kite I have, they can just run at me for days and WILL eventually catch me and there is ZERO duel potential against these guys, even when they have literally no damage items. It's very frustrating since I was under the impression that ADCs were supposed to be the counter to tanks. But instead there's challenging smite and Thornmail among a plethora of other items to counter adcs. It doesn't make any sense to me. That's like playing Rock, Paper, Scissors where you pick scissors and your friend picks paper but he tells you it's been coated in titanium or something and you're like, "Well what the hell is the point of the game then?"
tank > assassin > mage > adc > tank It's like Pokémon. The reason you have a team is so that you can prepare yourself for all circumstances. Not pick 6 water types and just stomp the yard.