Who said "A leader serves their people, not themselves."?

This quote is attributed to Lady Sif.

A leader serves their people, not themselves. - Lady Sif

"A leader serves their people, not themselves."

Lady Sif Leadership

"I am a warrior of Asgard, and I will not falter in the face of darkness."

"Strength is not measured by the power of one's blade, but by the resolve of one's heart."

"A true friend stands beside you, not behind you."

"We are forged in battle, but refined through compassion."

"A leader must be fair and just."

"Integrity is everything."

"One must take responsibility for one's environment."

"In this house, I make the decisions"