User blog comment:IamJakuhoRaikoben/Chapter 369: The Place Prayers Reach, Review./@comment-5598380-20140201001146/@comment-7418318-20140201095829

They thought that Humans couldn't possilby beat them, but Laxus and Natsu did it anyway, so they might now believe that Humans can't possibly break free from their control and be mistaken again due to underestimating them.

That's what you get when you think of your enemies as lesser beings instead of equals.