According to Chapter 4 of the Sai Satcharitra, for what purpose do saints take birth on Earth?

Chapter 4 of the Sai Satcharitra explains that saints incarnate for the benefit of others, with no self-interest involved. They descend to the mortal world when religion is in decay, when people lose sight of their ultimate spiritual goal, and when society is in disarray. The text states that saints come to protect the humble, poor, and weak, destroy irreligion, and re-establish the foundations of faith. Their primary purpose is to awaken religion and uplift the distressed, guiding devotees towards the ultimate truth before ending their incarnation once their work is fulfilled.