It does carry an element of truth! This tendency is too common and in the process we fail in enjoying ourselves with whatever we have and lose our precious years over fretting and fuming on things which we never achieve!
I agree. Man undervalues what he has. He likes to be in others' shoes. But if he gets what what others have, he will again desire something else that he has not and others have. This is psychological trait.
Its really a human tendency that we always want to achieve what we don't have and never think about those whom we had now. rather than this we should enjoy with our near residing people.