" Here’s how it happens: One person reveals something and waits to see if the other person will share something back. The reciprocity, if it comes, is a sign of understanding, validation, and caring. I’ve heard you, I understand and accept what you’re saying, and I care for you enough to disclose something about myself. An unresponsive partner—like a seatmate on a flight who puts on his headphones shortly after you make a comment—terminates the reciprocity, freezing the relationship. "

― Chip Heath , The Power of Moments: Why Certain Experiences Have Extraordinary Impact