Courtesy costs nothing. Lower the toilet seat after use. Let the people in the elevator exit before you enter. Return shopping carts to their designated areas. When you borrow something, return it better shape (filled up, cleaned) than when you got it.
"The success of machine learning depends on the ability to balance the trade-off between bias and variance in the models we build."
Sustainability isn't an option; it's a responsibility we owe to future generations.