Yoshimitsu felt offended, and after that, he was never allowed to change the name of the era during his reign, and that is why the Oei was the longest era before Meiji.
機嫌を損ねた義満は以後、逆に自分の生きている間には年号を変えさせなかったため応永年号は明治以前では最も長い年号となった。