If you measure productivity it is kinda easy to find the slackers who are working at home.
You warn them to get it together.
If they do not they get fired.
Easy peasy.
Bad managers are the only ones who cannot figure out how to make work at home equal or improve productivity.
According to my brother, it's easy to find them. But just working from home supports the mindset that they are "out of sight and out of mind" of the supervisors. As such, a lot of employees engage in idle time working from home when they ordinarily wouldn't if they were in an office environment with a supervisor physically nearby. As such, the supervisors are spending a lot more time micro-managing the workflow of individual employees, instead of managing the overall output of the departments.