User blog comment:Xilinoc/Ch. 540 - The Sword Five/@comment-8669536-20130605182414/@comment-28861328-20130607002058

Ah, but you forget! Oestu explained that. Somehow, White was created the same way Oetsu creates his Asauchi. Ichigo never had a need for one of Oetsu's swords, because his Hollow acted as the Asauchi. As Oetsu also said, the Hollow literally "became" Ichigo's Zanpakutou. Zangetsu is not the result of any Quincy powers. It is the result of Hollow Ichigo, or the entity we know as Hollow Ichigo. Why do you think Zangetsu was so insanely strong when Hollow Ichigo was in control? Because a Zanpakutou would naturally know how to wield itself.