Just a question for Xypherous about Orianna

I was playing Orianna some day ago and before/after playing one champion I dont know I try to understand it. In this case, I see a lot of player playing orianna so I try her and all of them playin a lot of mana regen, cdr, and bla bla bla... and I try to understand her:

Her passive is late game, scaling with AP and attack speed(Orianna has high base attack speed). Her W deals high base damage, increase you movement speed and slow enemies. ...

I understand the way I play her before was wrong because I try to play her as a cast-more-spells-as-you-can mage indeed. She is a mage when-you-abilities-are-in-cd-just-aa. After that my build change, I stop to buy cdr and buy only AP and tankiness on her and I start to win matchups I never win before. Am I right?