Why is this gym never properly sanitized and maintained? Trash is always strewn across the floors. The locker room always reeks of foul bathroom odors. The toilets are never flushed. The floors in the locker rooms are sticky and unsanitary. Why?

In the morning hours the workers are cleaning the gym. I've observed that with my own eyes. But that is definitely a question for managers

Hmmm... that, I can say never has been a problem in the women's locker room. I have noticed that the workers like to congregate around the desk. I have not seen any check around the gym or clean yet but, that is something to bring to the manager's attention.

All very good questions that I wish I could answer for you. However, the location manager should be able to answer them for you. It could be something as easy as it's a shift that they never work, so it is an unseen problem, and they just need to work that shift a couple of times a month to ensure that the issue is being taken care of properly. If the GM of the location doesn't help then go to the next level up, and submit a formal complaint with PF corporate offices to make sure you are heard and some type of action is taken to resolve these issues.