Yesterday I worked a (pre-planned) 11-hour shift at my day job. Scheduling agents is a rather tricky art, as the goal is to hit a tight balance between supply and demand. Too many agents, and there's a lot of dead time between calls, and everyone still has to be paid. Too few, and calls start backing up, sometimes severely. Some call-inducing events are known in advance, others happen when things start to break. Yesterday was more-or-less the right balance, i.e., I was actually needed for the overtime that was scheduled weeks in advance.