why does wip supply subinventory on work center take precedence over the wip supply sub in PIM

Summary: When we create new work definitions we have a supply subinventory set at the work center level which defaults as the supply subinventory for all components added to a work definition. Occasionally, we do not want to follow that logic and an item has a specific wip supply subinventory regardless of the work center. We apply that supply subinventory in PIM but new work definitions do not recognize it and still default to the subinventory stored in the work center. Is there a way to reverse the heirarchy so PIM overrules the work center instead