" It’s not enough to think people are happy. I want you to be a scientist about it: quantify it and equate it with performance. If something doesn’t match up, there’s a problem. It’s great to go to the pub with your team and bond. But it doesn’t do the company a lot of good if that bonding doesn’t actually translate into better performance. There are a lot of people I hang with just for fun. With my team I want that social aspect to move directly into performance. And "
― Jeff Sutherland , Scrum: The Art of Doing Twice the Work in Half the Time