Lead time encompasses every phase of fulfillment: order processing, engineering review, material procurement, production scheduling, manufacturing, inspection, packaging, and shipping. In make-to-order environments, lead time is the primary competitive dimension after price and quality.
Manufacturers typically distinguish between quoted lead time (what the customer is told), manufacturing lead time (time on the shop floor), and procurement lead time (time to receive materials). The total is often dominated by material procurement and queue time between operations, not actual machining or assembly time.
Reducing lead time requires visibility into where time is actually spent. Most manufacturers find that 80-90% of lead time is waiting — waiting for material, waiting in queue, waiting for inspection. Software that provides real-time queue visibility and intelligent scheduling attacks these wait times directly.