A friend and colleague who had been reading my recent posts on lean manufacturing posed an interesting question:
*“You’ve mentioned changeover or setup time as one of the biggest wastes in lean manufacturing. But the classic 7 wastes are:
- Overproduction
- Overprocessing
- Excess Inventory
- Waiting
- Transportation
- Motion
- Defects
There’s no ‘setup’ listed here. So where does it fit?”*
My answer was simple:
“It’s hiding somewhere in that list. Finding it is an interesting exercise.”
Let’s take a step back and look at each of the seven wastes more closely. The answer reveals itself quite naturally.
1. Overproduction
Any production beyond customer demand—or faster than the customer can consume—is overproduction. This is often considered the most serious waste because it triggers many others, including excess inventory and unnecessary handling.
2. Overprocessing
Overprocessing happens when we introduce tighter tolerances, extra inspections, or complex processes that the customer has neither asked for nor is willing to pay for. Investing in precision machines or deploying highly skilled people where they aren’t required only adds cost, not value.
3. Excess Inventory
This is inventory that piles up between processes. Why does this happen?
- Some machines have longer cycle times
- Some processes are temporarily unavailable
- And very often, one or more machines are under setup or changeover
Here lies our first clear answer: setup time directly contributes to excess inventory. When a machine is busy changing over, upstream or downstream processes continue producing—or wait—creating inventory buffers.
4. Waiting
Waiting occurs when resources are not synchronized:
- Operators waiting for machines to finish cycles
- Machines waiting for operators, tools, or materials
- Parts waiting because previous batches were rejected
- Materials waiting because the machine is still under… setup
Once again, changeover time quietly shows up as waiting waste.
5. Transportation
Transportation waste refers to unnecessary movement of materials due to poor layout or unclear process flow. It can also be caused indirectly—when defects force materials to be quarantined in remote locations or when excess inventory needs to be shuffled around to make space.
6. Motion
Motion waste is about people, not parts. Poor ergonomics, awkward reach, bending, lifting, or unsafe movements all slow down the process and reduce productivity. This waste directly affects speed, flow, and operator well-being.
7. Defects
Defects are perhaps the most obvious waste—leading to scrap, rework, customer complaints, and firefighting. I’ve discussed this in more detail in an earlier post, so I won’t dwell on it here.
So, Where Is Changeover Waste?
The answer should now be clear.
Changeover (setup) is not listed as a separate waste because it is embedded within other wastes—especially excess inventory and waiting.
Its impact is real, significant, and often underestimated.
Understanding this connection helps us see why reducing setup time is such a powerful lever in lean manufacturing.
Armed with this perspective, I hope you’ll be able to observe your own workplace more critically, identify hidden wastes, and take meaningful steps toward eliminating them.
Good luck on your lean journey.
#LeanManufacturing
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