There's no magical cutoff at 3-6 months, but the game theory is that the longer the relationship, the more of a repeated game there is, and the less socially de

There's no magical cutoff at 3-6 months, but the game theory is that the longer the relationship, the more of a repeated game there is, and the less socially destructive things you'll likely do. If I'm going to live with a neighbor for ten years, in addition to purely friendly reasons, I'm going to say hi to her and get to know her. Whereas at a hotel I'm overnighting at, if I'm not in a chatty mood, I don't see the reason to oblige a neighbor's request for a 20 minute chat.