Non Intervention!!!
Everyone has a his unique way of living which he doesn't wants the other person to know or understand to share. He would be happy in his own company and the ingress of others would be treated as aliens who have entered their comfort zone. I had an european colleague, with whom i had lunch many times. While my plate was filled with rice n curry he had a salad or juice. I had offered him Indian food once, he apprehensively declined with a simple 'Thank You'. I never compelled him later as I knew he had his own way of habits which he didn't wish to change even in his diet. Some people do understand the need of space for others. The practice of Non Interventions is also a Yoga. Right from scheduling a meeting or to knocking one's room door, is a sign of good practice to avoid non intervention. Not sure if to be applied for surprises...