when you realize cas never got a chance to see dean mourn him. to see what his death did to dean. how it broke him completely. SHATTERED. he never saw dean's utter despair. anger. complete hopelessness. he only ever saw dean's joy when he came back. and so cas figured that his death simply didn't affect dean all that much. that dean could be happy with Cas gone. that Dean could go on. Move on. cas never understood that this joy, this hope, this smile on dean's face after he came back was ONLY BECAUSE HE CAME BACK. CAME BACK TO DEAN.
With a lead of nearly 2.5 lightyears, the race has been called for Uncle Iroh early in round 5. He therefore now moves on to his next potential victim, our very own heavenly news anchor, Castiel of Supernatural. Begin the suffering.