I am able to reproduce the inconsistency behavior, and I hope this shade some light.

here is my UI policy for a specific category called:

Here is a Try it screenshot where it shows hidden variable based on the UI Policy:

But if a refresh it few times it shows the correct variable "Property Name". 

Here is the variable setup for Amount:

The "amount" variable also seats on another UI Policy with "show/visible" where we need it be visible under a different category.

Any guidance or direction greatly appreciated.