User blog comment:C4bal/Corki in the Tank Meta. How to./@comment-5235176-20150613220935/@comment-24036535-20150614060846

Because under the circumstances you described, especially with the way the game is progressing, the minimal tank power you gain from that is going to reduce your dps, while still not giving enough survivability to live. The game works in a simple way: If you're a carry, be you a mage, ADC, or assassin, you focus on avoiding damage, not sustaining it. If you're taking damage, you aren't doing your job right. Hence why Banshee's Veil, GA, Scimitar etc exist, they allow you to avoid damage or act as "get out of jail free" cards in case you mess up.

Don't sub out two items to get a two weaker but defensive items, sub out one to "get out of jail free" once. ie That Blitz pull becoming a problem? Banshee's, now you get to make one mistake at no cost. Enemy assassin killing you just before you get peeled? GA to buy you those extra seconds. Lot's of CC getting piled onto you? QSS to clense the big stuff.

Going slightly defensive won't save your life though, especially as an ADC, if the enemy is close enough to deal damage to you in the first place, that extra armor and health won't save you.

Oh, and IBG outright does less damage than Triforce, you know, weaker passive, same AP, no other offensive stats. And LW gives more armorpen than BC does, without having to stack it. Corki may be a caster-carry, but he still get more out of his AAs than his abilities.