Leave it better than you found it.
I first heard the phrase from my father in relation to camping. When you're leaving a campsite, you should try to pick up any trash you see, even if it isn't your own. The goal is to leave the site even better than it was when you first arrived, so the next campers have a positive experience.
"Leave it better than you found it" is my personal motto, and one I truly take to heart. I strive to improve the lives and circumstances of those around me, and I measure my success through my ability to elevate the individuals and businesses I encounter.