We work on the throughput, uptime, and labour of the plant, where a manufacturer's cost is set.
We work on sourcing and supplier terms, usually the largest single cost the business carries.
We work on quality and reliability, and the cost of getting them wrong.
We work on pricing, and on the cash tied up in inventory and receivables.
We work on the floor, where the cost is made, and on the procurement and pricing that decide the margin around it. We measure what is actually happening before we change it, and we build the improvement into how the plant is run and measured, so it holds after we leave.