Is the number of hours the worst thing about investment banking?

Most junior bankers will tell you that the worst thing about the banking lifestyle is not the number of hours required per se, but the unpredictability to those hours.  Said differently, that you have NO control over your life, as you are expected to be reachable at all time, day and night. This lack of control makes it extremely difficult to schedule time to see friends and family.  Analysts and Associates find themselves routinely having to cancel dinner plans, weekend plans and even vacations at the last minute.  Many bankers, after a few months on the job cease scheduling events altogether, for fear of having to cancel.