You want to know how a minor secondary character gets picked to die? The son of a bitch with the longest name is the one that goes, dude. I had my choice of Hell-Devourer, Sword-of-Cowards, Blood-Spilled-for-Freedom, Mother-of-Terror, and My-Sword-Cleaves-Evil — and Blood-Spilled-for-Freedom won the toss, because I am NOT typing that name a million times in the next seven books. Don’t hold your breath for the rest of these bastards living forever, either.
On the other hand, guys named Sam and Fred are nearly bullet-proof.