Vishnu Purana gives a slightly different account here. When Vishnu was pleased with Dhruva's tapasya and asked him to ask for a varadāna (grant of wishes), a said that he (being an uneducated child) did not know how to sing the praise of Lord Vishnu, and therefore asked the varadān of a knowledge of stuti (hymn in the praise of Vishnu). Other persons would have asked for worldly or heavenly pleasures, or for moksha at most, but Dhruva had no personal desire. Renunciation of all desires is regarded to be essential for eternal peace in Hinduism: this is the meaning of Dhruva-pada. That was the reason why the Saptarshis decided to give Dhruva the most revered seat of a Star.