because using other people’s norms in the normal way is one thing (Rienzi, Das Liebesverbot, and Die Feen.)
adapting them for your own purposes is another, Der Fliegende Hollander, Tannhauser, Lohengrin, but
designing your very own with your purposes in mind from the BEGINNING is enTIREly another! (Der RIng (Rhinegold, Walkure, Siegfried, Gotterdammerung,) Tristan, Meistersinger, and Parsifal.
(those are the 13 opera’s by Wagner, the first two of which I believe never saw performance during his lifetime, the next three were him (I believe) adapting existing operatic styles (german, italian, and french, I think.. (Maybe I’m paraphrasing or remembering incorrectly)
and the remainder are his own, mature music dramas.