mayy ekānta-matir nānyan
matto vāñchati tattva-vit
When the demigods finished offering their prayers, they anxiously waited for their enemy Vṛtrāsura to be killed. This means that the demigods are not pure devotees. Although without difficulty one can get anything he desires if the Lord is pleased, the demigods aspire for material profit by pleasing the Lord. The Lord wanted the demigods to pray for unalloyed devotional service, but instead they prayed for an opportunity to kill their enemy. This is the difference between a pure devotee and a devotee on the material platform. Indirectly, the Lord regretted that the demigods did not ask for pure devotional service.