For years I swam with a group of friends at a local pool before we all went off to work. I was responsible for picking up two mates on the way to the pool. The only thing that got me out of bed was the fact that I knew my friends would be waiting for me. And the expected pick-up was the only reason my friends got out of bed each of these mornings, too.
Yet, as much as we all enjoyed the swim, invariably, if one of us had to cancel, none of us would go – we could all easily put an excuse in the way. Such is the power of groups.