TOC focuses on three measures of organizational performance : throughput, inventory, and operating expenses. Throughput is the rate at which an organization generates money through sales. In operational terms , throughput is difference between sales revenue and unit level variable costs such as materials and power. Direct labor is typically viewed as a fixed unit level expense and is not usually included in the definition. With this understanding, throughput corresponds to contribution margin. Inventory is all the money the organization spends in turning materials into throughput. Operating expenses are defined as all the money the organization spends in turning inventories into throughput . Based on these measure, the objectives of management can be expressed as increasing throughput , minimizing inventory, and decreasing operating expenses.