According to Chapter 4 of Sai Satcharitra, why do saints take birth on Earth?

Chapter 4 of the Sai Satcharitra explains that saints incarnate on Earth during times of moral and spiritual decay. This happens when religion is in decline, when people disrespect religious teachers, ignore proper conduct, and become obsessed with worldly attachments like wealth and status, turning away from the ultimate goal. Saints descend to awaken religion, protect the humble and the weak, destroy irreligion, and uplift the distressed. Their incarnation is described as being purely for the sake of others, with no self-interest involved in their mission.