Raw materials or components utilized, direct labor, and manufacturing overhead are all expenses that are included in an ending work in progress inventory for most manufacturing processes, Materials, salaries and benet costs for workers, subcontractor costs and expenditures are often included as components of a WJP for construction or other long projects In any case, establishing the value of work in progress may take a long time, therefore businesses strive to reduce WlP as soon as possible before the end of the accounting period