Even beyond dating, I believe any type of short or long relationship is sustained by curiosity, from the mundane 'why do you like this hobby' to the major 'how are you handling grief over xyz'. And, mutual curiosity is the spice of great conversations.
when you’re younger and dating you might not notice it, but as you get older you start realizing how important curiosity is. someone not asking questions, not wanting to know you… is an instant ick.