Incites to demand the throne of sleep.
Once Kumbhakarna desired to attain the throne of Indra. So to please Brahma, he started observing penance. Seeing this, the lord of gods Indra got worried. Indra prayed goddess Sharda and got the promise of protection of his throne. On the other side, Brahma was pleased by Kumbhakarna's penance. But at the time of demanding the throne of Indra, goddess Saraswati sat on his tongue and made him speak Nidrasan, instead of Indrasan. Therefore, he remained constantly asleep. Thus, due to Mother Sharda, Kumbhakarna's penance failed.
This incident indicates the power of word. This incident indicates that if we please Brahma, but if we do not please Sharda, we can not get desired result. Moreover, if we develope demon like tendencies like Kumbhakarna, then also the mercy of Saraswati will be useless for us.