As long as it benefits even one being you have to, without any sense of discouragement, go on.
The Bodhisattvaʹs aspiration and actions are powerful because from the very beginning when a Bodhisattva embarks on the Journey of the Bodhi Path, he aspires to work for the benefit and liberation of all sentient beings with a very determined, definite and powerful intention.
Because of the sincere resolve that is within this aspiration, whatever actions need to be performed to benefit and liberate beings are performed with great power and tirelessness.