Can I Stop Inspecting?

When educating on the types of waste, I find that most people initially have a hard time seeing inspection as a non-value added activity.  Usually, it is for one of two reasons: 1) making sure the quality is in the product is valuable to the customer or 2) it is a legal requirement.  While there is not much we can do for #2, we can change #1.  I always start with the definition of value added.  I use one that I learned from the Lean Learning Center.

(Full Disclosure: I have worked with Lean Learning Center for about 4 years now, so you will see their influence in some of my definitions.  The link is meant as a credit to my source.)

The Definition of Value Added:

1. Must be something the customer sees as value and is willing to pay for

2. Must alter the process output, the product must change

3. It must be done right the first time

All three criteria must be met in order to for the activity to be value added!

If any of the three criteria are NOT met then it is non-value added. Almost right away people see that inspection does not physically change the product.  This allows them to now see inspection as a non-value added activity and move forward with doing something about it.  Not accepting it as part of the process.

You can’t just eliminate an inspection point because it is non-value added.  Now you have to understand two things: 1) How effective is it? and 2) Why is the inspection point there?

How effective is the inspection? The first questions asked should be: How many defects are we catching at this point?  and What are the consequences of not catching it?  If it is found that the inspection sees a failure rate of under 1% (which I have seen several times), then why do the inspection?  This is where understanding the consequences of not catching a defect comes in.  If you don’t catch the defect does something catastrophic happen?  Or is there now much of an impact on the process/system?  If something catastrophic would happen then you may decide to keep the inspection until you find the root cause of the 1% failures and have confidence in your process not to create the failure.  If there is not much of an impact on the process/system then I would eliminate the inspection.

Why is the inspection point there? If you see a high failure rate at inspection or if a single failure can be catastrophic, then this would be a good place to look at doing some problem solving.  Find out what are the failures at this point and do some problem solving around these issues.  When the failure rate becomes small or zero then revisit the “how effective is the inspection” questions.

Eliminating inspection can really help reduce the waste in your process, but only if you eliminate it for the right reasons.