There is a verse in which Srila Rupa Gosvami says, avyartha-kalatvam: [Cc. Madhya 23.18-19] a devotee should be very much careful to see whether his time is being spent unnecessarily. He should ask himself, “Am I now engaged in maya’s service or Krsna’s service?” This is a symptom of an advanced devotee. Nama-gane sada rucih: such a devotee is never tired of chanting, singing, or dancing. The word sada means “always,” and ruci means “taste.” A devotee always has a taste for chanting Hare Krsna: “Oh, very nice. Hare Krsna, Hare Krsna, Krsna Krsna, Hare Hare/ Hare Rama, Hare Rama, Rama Rama, Hare Hare.” This is taste. Of course, this taste takes time to awaken, but when Rupa Gosvami was chanting he was thinking, “I have only one tongue and two ears. What can I appreciate of chanting? If I could have millions of tongues and trillions of ears, then I could relish something by chanting and hearing.” Of course, we should not imitate him, but the devotees of the Krsna consciousness movement must at least be very careful to complete their sixteen rounds, their minimum amount of prescribed chanting. Nama-gane sada rucih: we have to increase our taste for singing and chanting Hare Krsna.

From: Teachings of Queen Kunti, by Srila Prabhupada