Process Costing and Spoilage Example Ending work in process was 4,000 units each 100%complete as to direct material costs). Spoilage is detected upon completion of the process. Spoilage is typically assumed to occur at the stage of completion where inspection takes place. 海南大学董建华讲授 7-12 海南大学董建华讲授 7- 12 Process Costing and Spoilage Example Ending work in process was 4,000 units (each 100% complete as to direct material costs). Spoilage is detected upon completion of the process. Spoilage is typically assumed to occur at the stage of completion where inspection takes place