S.B. confirms it that if someone follows all the rules and regulations very nicely but doesn't come to Krishna it is useless, and similarly if someone comes to Krishna, even if he doesn't follow very nicely, he is perfect. Also, B.G. 7/19 says that the wise man after many births comes to know that Krishna is everything. So Krishna is central. So we may begin our chanting with some motive, but that is not the final stage. Love of Krishna is final, and how can we develop that unless we are chanting and thinking of Krishna?
Letter to Hayagriva, 26 September, 1970