Glenn hasn’t been able to find a replacement for his assistant manager, so he takes on the both roles for the day. Glenn struggles to get everything done in one day and suggests that he may have to stop sleeping. Even though he’s doubled his effort, his output hasn’t doubled; it has diminished. At a certain point in the production function, additional workers are not as productive as the ones before them. For Glenn, this would be represented by the additional hours that he’s worked in the day. Specialization allows workers to focus their time on tasks that they are good at, like setting schedules or ordering products. Just because a worker can do all of the functions, doesn’t mean they should do them all.