Part time employee working from 8:30 AM to 1:30 PM refuses to come in early to help her coworkers: 'When I say early, I mean like 3 AM.'

Why should she have to help everyone else get their work done?

There are some downsides to being an incredibly hardworking, competent employee. One downside is that you're often "rewarded" for your good work by being asked to do more work for the same amount of money. Sometimes, that's what striving employees want! They do as much work as possible to prove to their employer that they can handle the workload of a higher position. Deep down, they know they're kind of getting exploited, but they are willing to put up with that for a little while if it means securing the bag in the future. 

Not every employee is a striver, and that's okay! There is a lot of value in having some employees who are incredibly competent in their position, and don't have any real desire to climb the corporate ladder. They want to show up, do their work well, and go home without any pressure to be better than anyone else and their department, and that's great! If you can keep employees like that happy, you can keep them in their positions for years, offsetting the pesky costs of hiring new employees. 

While some unambitious employees are reliable and steadfast, others are kind of lazy and willing to do the bare minimum to avoid getting fired, but nothing more. The employee in this story has been doing the bare minimum at his job for years, and his bosses are finally onto him.