Board Thread:Questions and Answers/@comment-25506085-20141013044638/@comment-5398287-20141013161640

TennoHaineko wrote: Xilinoc wrote: TennoHaineko wrote: Stefan (Shikai - "Rust & Shatter") wrote: (...) 3. Aizen didn't really need a Bankai, since whenever someone managed to injure him, the Hogyoku would simply make him stronger, and that was part of Aizen's plan. In Aizen's final fight against Ichigo, they were both on a level where a mere Bankai probably wouldn't have done much damage anyway. Aizen also thought of himself as being superior to Ichigo, and if he were forced to use his Bankai it would prove that they were equals. Simply put, he was too proud to use his Bankai. (...) A bankai is between 5 and 10 times as powerful as a Shikai, and he didn't even use his Shikai against Ichigo, who knows, maybe it could turn at least a bit the battle's winner. But anyway, i ask myself why Aizen hasn't used his Zanpakuto in the battle with Ichigo, maybe overconfidence? Or maybe when he evolves from the Hogyoku he can't use it anymore? It was overconfidence. That, and he wanted to test his new strength against Ichigo, and putting Ichigo under complete hypnosis wouldn't allow him to do so properly.

Why didn't he used his bankai when he figured out that Ichigo was in a completely different scale of power? Because at that point, he was so far-gone over the edge of madness, arrogance, and insanity that he was too stunned to react properly and rationally like he would have in his normal form.