Theologically speaking they do when they claim at Armageddon god will cast down balls of fire and destroy all who rejected him and did not worship him.
Which by the JWS proclamations and teachings, that's about 99% of the world's population.
The end of the world in a religoius sense, not the end of the world like the entire world is going to be completely destroyed.
Its clearly identified as a fear mongering apocalyptic religious publishing house.