Lean is obviously a lot more than just elimination of waste activities in processes. It has the power to impact other areas of operations.
One of the projects I managed while I was a continuous improvement engineer for Thomson Plastics was for an injection molded flywheel for a handheld leaf blower. We were having quality issues internally that caused significant scrap rates but some of our quality problems made their way to the customer. We were running this part on two injection molding presses (one with a high tonnage rating and one with a lower rating) and had inconsistent work cell layouts and manual processes.
By using time studies, operator input about the process steps, layout standardization, shifting the production schedule from being split on two presses to keeping it on just the lower-tonnage press, and other changes we were able to reduce excess waste activities, shorten the cycle time, and reduce the defect rate by 90%.
In addition to reducing resources consumed by this process, we were able to open up press capacity (especially on the large-tonnage press removed from this process). With the freed-up time, we were able to get started on other orders of larger parts (read: higher margin) while maintaining the same resource levels.
By freeing up capacity on constrained machines and processes and using that time on manufacturing products customers have ordered, we find that lean can be a big revenue driver because of the more efficient use of resources.