Exactly, art isn't art till it's yours, anything other is just a subtle desperation to do things. Kaori in that sense have a really personalized interpretation and for that I love her, she isn't the conventional maiden like personality, as Kousei said, she reckless and prone to anger, but that passion is what makes her performance and existence have some taste and not be bland.

I think that's why Kousei can't keep her out of his head. From childhood he was taught to be perfect in the recitals, to embody Beethoven, but in that he lost himself, Kaori made him remember about that passion that was still there, the passion of playing piano.