Consistency and Discipline.
As you get older and more experienced in life, you start to realize just how rare consistency towards anything is and how undisciplined people can be, especially regarding something that doesn't effect their personal lives. When you meet or deal with someone who has one or both of these qualities, they begin to become your favorite and most respected quality of their personality. Time is a limited resource and something we all value, and when someone is consistent to a point you can set your watch to, they help manage that precious resource.