This is essentially a summary of all the different types of reciprocators—whether it is unconditional love, conditional love or indifference. Krishna is going to explain why it appeared that
He did not reciprocate, but in fact, was reciprocating. This is what really brings out and enhances Krishna’s personality —especially in the case of devotees—when it externally appears that Krishna is invisible and is not reciprocating. When it appears that Krishna is not reciprocating, He is actually reciprocating, because He is intensifying the affection and unconditional love that devotees have for Him. Krishna says to the gopis, “For those who are actually situated on the platform of prema (pure love), I do not reciprocate with them because I want to intensify their attachment, love and affection for Me. Just like a person who once had a great wealth and later lost it, he does nothing after he lost it except think of how to get that wealth back again.”
Lectures from a Disciple, "Serving a Person", Pg 57, 4th Paragraph