It is a very interesting and true observation that many are not aware of. This question was asked to The Mother and here is what She replied.
‘This afternoon I forgot one thing. The day before yesterday I spontaneously prayed to You to destroy all that is hostile in me, as Durga kills the Asuras.
Durga does not kill the Asuras; she reigns over them and makes it impossible for them to destroy.
In essence, all is the Supreme Lord and has to return to the Supreme Lord for an ultimate transformation.
Death is only an expedient — surrender is the victory.’
(Ref. https://incarnateword.in/cwm/19/11-october-1967)
Destroying the form does not destroy the being, the force, the energy that is behind the asura. That is why the Mother and Sri Aurobindo have decided this time to dissolve, convert or transform the four original Asuras. To destroy them would mean destroying nearly whole of humanity that harbours the Asuric forces happily in its bodily house. Of course, emanations of these Asuras can be destroyed, as far as their gross or subtle forms are concerned. But then they return in other bodies and other forms. Whereas when an asura surrenders and is converted, he becomes a powerful instrument of the Divine. That is the plan working now.
Affectionately,
Alok da
