Who said "I've learned that sometimes no is the most powerful word."?

This quote is attributed to Joan Holloway.

I've learned that sometimes no is the most powerful word. - Joan Holloway

"I've learned that sometimes no is the most powerful word."

Joan Holloway Power

"I'm just a girl in an office"

"A woman is her looks. That's just the truth."

"I don't think about the future. It hasn't happened yet."

"Sometimes I think about how things could have been different."

"Power without control is just destruction."

"Power is not about control, it's about influence"

"The world doesn't need me to be the hero. It just needs me to be dangerous."

"The claws come out when I need them to."