Time (Kaala) is divided into four ages, or yugas, that make up a cycle. The Avatar descends in the time of the most dire need – the Kali Yuga (Age of Kali). Kali is the age of great delusion, where our experience of life is most distant from reality. Sadashiva says reality is eternal bliss and complete fulfillment in every moment. Meanwhile, what we feel inside is distinctly opposite. This duality, between reality and experience, between what you believe and what reality is, is what our rishis signify as the beginning of “Kali”, the mark of Kali.
The accumulation of this delusion has reached the point where if humanity does not fix itself now, it will end up in its own collapse. This is the reason for the descent of the Avatar.