Thanks for your insightful comments. Something for me that falls under the rubric of "normal reciprocity" is an explanatory apology. If a friend has agreed to

Thanks for your insightful comments. Something for me that falls under the rubric of "normal reciprocity" is an explanatory apology. If a friend has agreed to meet me for coffee somewhere and arrives 30 minutes late and just says "Sorry!" with no explanation, I get peeved. I feel deserve some explanation as to why 30 minutes of my life was wasted.