User blog comment:ClariS/Why Xerath's Passive is Bad/@comment-9713132-20130318110601/@comment-9713132-20130319043634

Apologies, I mis-read the title statement of your blog post.

However, I still stand with the second part of my comment in which I find that it does have a place in Xerath's kit. He's an immobile champion in the early game that is a lighted bullseye for ganks - that armor is, IMO, meant to help his early game. Also, while Xerath isn't always going to face an AD champ mid, note that AAs do more damage early-game than their primary spells, so armor on Xerath actually makes sense. He's meant to be a turret and played as such - late game, a far placed turret, but early game, someone that stays and fight instead of run away, so that armor buffs his lane durability.

Perhaps it doesn't synergize with his 'late-game' gameplay, but in lane he has no allies to hold off an attacker at bay and thus it's quite logical that the most immobile champion in the game is granted extra durability.