User blog comment:B214/Question and Answers 6/@comment-24098614-20170331205750/@comment-24098614-20170331210719

The reason is that Dragons pride themselves in their power, and love to upstage one another because Albion and Ddraig used to fight each other to prove who was stronger the question now is Ddraig irrelevant now in the story because Issei's power is tied to his Sacred Gear.