When a demon like Hiraṇyakaśipu, despite his elevated position due to severe austerities, begins to tease a devotee, he begins falling down, and the results of his austerities dwindle. One who oppresses a pure devotee loses all the results of his austerities, penances and pious activities. Since Hiraṇyakaśipu was now inclined to chastise his most exalted devotee son, Prahlāda Mahārāja, his opulences began dwindling.