Current behaviour:

For several Categorys or SubCategorys (Helpdesk Customizer - Category), our organization does not have SubCategorys or Items assigned by design because for some services we do not need to be more granular.  

Our  Incident (for example) Templates are assigned SubCategory as a mandatory field because, if the SubCategorys exist under the chosen Category, we do need the further classification for our reports.  Unfortunately, even if no SubCategory exists under a  chosen Category,  the mandatory field still requires us to use a SubCategory  (we cannot save the edit and are unable to select a SubCategory).  

Suggested behaviour:

If there is no SubCategory/Item configured for the parent Category/SubCategory (and record templates use SubCategory/Item as mandatory fields), have the mandatory field determine that if no SubCategory/Item exists, do not consider it a mandatory entry.