"Life and death coexist. Allow death to exist or this world will have no meaning."
Ferdinand and the others were all against it at first.
But after eons passed and they went through a lot, and yet, never perished, they finally understood.
Life without death becomes meaningless.
All primordials understood this.
Their seemingly unlimited time made them bored with life and pushed them to chase after death instead.
Likewise, they needed to let other living beings fulfill their purpose and follow their fate.
Ferdinand understood this too after the ones he had tirelessly revived still left so they could move on to their next life.
In the past, they may have been able to delay it for some time, but eventually, life must go through death in order to live again.
Ferdinand and the other primordials will go through it as well someday.