When you read books on biology and evolution, the end goal of every organism seems to be just one thing. Survival. Since no living being can survive infinitely, reproduction makes it possible for the species to not die out completely.
There is also the concept of carrying capacity. If you took some bacteria and put it in a Petri dish with food. The bacteria will grow very quickly till it consumes everything in the Petri dish and then its population hits a wall before it completely collapses.
Two years ago, a virus called Coronavirus entered the manmade Petri dishes called cities. Without cities, it would have been impossible for any virus to transmit as quickly.
Its biggest problem seems to have been that it killed its host. An even bigger problem was that the host fought back. Funded with Billions of dollars of government money, Pharma companies produced vaccines that could start killing the virus. The companies held on to all of the profits despite making very little investment, but that is for another blog. It is the story of almost every innovation known to mankind.
The process of mutation that the virus is undergoing is to find an optimum where it can spread across the Petri dish without triggering the worst reactions from its hosts. The current numbers make the alpha and the delta waves look minor in comparison. France is recording 300,000 cases, whereas earlier it had not even recorded 100,000. America looks set to hit a Million cases a day at any moment.
The current mutation is not terminating its hosts with the same ferocity.
Due to the large numbers, the absolute death numbers are comparable to earlier waves but in relative terms are quite low.
The virus is mutating because it needs to survive. It needs to ensure that the hosts survive so that it is not eliminated completely.