Krsna is so merciful that He always thinks of how to liberate the conditioned souls from the material platform. It is for this reason that Krsna incarnates, as clearly indicated in the Bhagavad-gita (4.7):

yada yada hi dharmasya glanir bhavati bharata
abhyutthanam adharmasya tadatmanam srjamy aham

“Whenever and wherever there is a decline in religious practice, O descendant of Bharata, and a predominant rise of irreligion — at that time I descend Myself.” Krsna always protects the living entities in many ways. He comes Himself, He sends His own confidential devotees, and He leaves behind Him sastras like the Bhagavad-gita. Why? It is so that people may take advantage of the benediction to be liberated from the clutches of maya.

From Srila Prabhupada’s purport to Cc Adi 8.11