Often used in reference to events with consumable items like food or supplies that were not fully used up. They ordered too much pizza; half was left over after the party.
Pro Tip 2/3
Not Wasteful
Implies that the remaining items can be used later rather than being wasted. Don't throw away the paint; we can use what's left over for touch-ups.
Pro Tip 3/3
Unexpected Surplus
Sometimes indicates a surprising or unplanned amount remaining. We had a bigger turnout than expected, but we still had drinks left over.