It's a mistake to expect benefits from any pose. Expectations make you restless because if you fail to get what you expect, you feel miserable. Yoga practice is an act of adoration to the Lord. You do it because it has to be done. If you have this mental attitude, your selfishness disappears and the benefits come.
Asanas: 708 Yoga Postures (ed. New World Library, 2002) - ISBN: 9781577314028