When a requisition approval workflow is triggered, historically it would be based on the hiring manager i.e. the manager who has created the requisition - for example if you have an approval workflow for sales requisitions, and the hiring manager is in sales, then the sales workflow will trigger. If you also have an approval workflow for finance requisitions, and the hiring manager is in finance, then the finance workflow will trigger.
However, if the hiring manager in sales entered a requisition for the finance department, this would previously still trigger the sales workflow as the hiring manager is in sales - the job detailed in the requisition did not get considered.
The workflow is now based on the job detailed in the requisition - the hiring manager is not relevant. As a result, all other options to restrict a requisition workflow have been removed - only sites, department and company can be used to limit these.
So if a hiring manager in sales creates a requisition for a finance role, the finance workflow will trigger and not the sales workflow as before.