Q 618. Are there any exceptions to the generally true statement that "Process improvements do not result in a change in specification limits"? Provide examples to support your answer.

 

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May be in olden days this statement would have been true, "Process Improvements do not result in specification change". In todays modern world, where we see new innovation left and right on every corner, not one but there are several such example where specification limits were changed. 

 

Examples 

1. Earlier if customer needed a spherically hollow part with say 3mm thickness, they shared drawings with 2 'C' type parts which get welded and then become sphere. Now with innovation in metal 3D Printing, with little changes full Spherical parts will be 3D Printed. Now Specification Limit (drawing) changed completely, as a single solid part. In My Previous Organization we printed such a part for a defense customer.

 

2. Earlier if you need a Burger after ordering we used to get in like 15-20 Minutes. Now with Innovation by KFC & Mc Donald's they deliver within 5 min. Now Customer specification (expectation) changed, We need Burger with in 5 Min of order.

 

3. Earlier for booking a cab we need to inform well in advance in 2 days or 1 week that we need a car on so and so date. Now after innovation by Uber and Ola, The movement you decided you need a car, you can get it in 5-10 minutes of wait. Decided to change the destination no worries go ahead, Customer specification limit (expectation) changed now.

 

4. Earlier when you order grocery online / Food Items in initial days they used to take like 4-5 Hours. Now with innovation in delivery apps, In 30 Minutes you will get your food items and grocery (Zomato, Swiggy). 

 

5. When Dominos said "Delivery in 30 minutes or free" then specification limit for delivery time changed.

 

6. Earlier if you buy any items online or in showroom there was no refund option. Now after innovation by Amazon and Flipcart in supply chain they guarantee 30days refund guarantee Customer specification limit (expectation) changed. Now almost for all the products you have return policy if you do not like it.

 

7. Earlier for Mobiles there was not even 2GB storage capacity. After innovation by Iphone, Samsung, Nokia and now Customer specification limit (expectation) changed its 128, 256, 512GB. For Ram as well  Customer specification limit (expectation) changed 16GB ram for Mobile is no longer fancy its a new specification for some customers.

 

8. Mobile internet speed, Earlier for Mobiles specification was 2G then it changed to 3G later 4G and currently 5G.

 

9. Earlier Laptop users were looking for 256GB hard disk and now Customer specification limit (expectation) changed 1TB and 2TB is like minimum need now, same also goes for Ram of laptop.

 

10. Sports cars when they initially stated speed was as far as what I remember it was somewhere around 150 KM/Hour. Now Customer specification limit (expectation) changed 304.7 MP is the new fastest speed for sports car. 

 

Summary

All the innovations that happened in one company have become a norm in that particular sector / Industry. So ya customer specification has been changed and same were expected from other competitor suppliers, as on when a new innovation happened.

It is believed that process improvements do not always contribute to change in specification’s limits. We brought in a machine learning data model to one of our projects and defined recall rates i.e. the capability of the model to identify the true sanction organisations as an interval between 90% and 98%. However, the control limits showed that within a volume of 1 million, we were with 92%and 94% percent control. Now the question is the upper specification varies slightly more than upper control limit. So there is always a scope to bring specification from 98% to 95% as one would think as a rational thinker.

 

However, if there are reasons to keep the gap broad between upper control and upper specification limit due to regulatory requirements such as aircraft wing span in a runway, then specs must not be reduced or changed is my opinion.

"Process improvements do not result in a change in specification limits" is close to accurate, this implies that modifications to a system's internal operations have no direct impact on specification limits, because specification limits are set by customer requirements. However, depending on certain scenarios, there are exceptions to this condition, Examples:

Changes in Customer needs:

The specification limitations need to be changed in case of any significant changes in the needs of the customer. Specification limits need to be adjusted due to process changes made to accommodate new customer demands or needs.

Regulatory changes affecting industry:

Modifications to industry standards or laws will require changing specification limits, Government might impose stricter rules which might require process improvements, which could have an impact on the specification limits.

Technological Enhancement:

In the course of time, processes achieve or overshoot the expected metrics such as line efficiency, In such situations, the company might decide to alter the specification limits to have revised Metrics in place with new process capabilities.

Cost Reduction through innovation:

Specification limits will have to be changed if process innovations reduce costs without affecting quality, safety and is consistent so that the changes can be made in specification limits.

Continuous Improvement:

Continuous improvement is a part of many organizations where with tools like Kaizen and other multiple initiatives, processes are relooked into for enhancement, this activity can also challenge the specification limits and might result in changes post implementation of improvements in the process.

I strongly believe there are exceptions to the belief that "Process Improvements do not result in a change in Specification limit".

 

Let me explain this, with a couple of examples:

 

Imagine a software team developing a product. The team is doing unit testing manually. Soon, the team decides to have automation testing and proceeds with that. This is certainly a Process Improvement that is happening because this will have - a reduced manual effort from the developer, quick identification of issues, easy repetitiveness of testing(all scenarios and with different set of data), improved development cycle time,etc.... As soon as there is an automation testing(Process Improvement) involved, the customer may talk about 'Code Coverage'. The customer might say that 'Code Coverage' should be  80-85% which is your customer specification limits for your 'Code Coverage'. As your automation process gets more mature, the customer might be forced to change it  a more rigorous Specification limit say to >=95% (lower limit). Therefore it is possible that doing the Process Improvement can result in changing the  Specification limits.

Another Example with a different flavour that i want to highlight:

 

Consider 'Definition of Done'(abbreviated as DOD) in a Scrum environment. DOD is akin to being a quality checklist. When a product backlog item (a simple explanation - that can capture a product requirement)
is to be considered as 'Complete', it has to meet the DOD [For eg, in a software product development, the DOD may have steps that can be like say coding, peer-reviewing, unit testing, system and integration testing, pre-prod testing and deployment...]  While the DOD is owned either by the Scrum team or by the organization that develops the product(service providers), the customer who also may be part of the Scrum Team(say a Product Owner) can have a say in the DOD. Now the steps in the DOD are like the Specification limits.

 

Imagine(a hypothetical scenario) Now that you have a Continuous Integration process, which is usually capable of automating your process till your Code is put in the Quality Assurance(QA) environment(if there is one such environment or any environment where all kinds of testing can happen) where functional testers would be able to test your code and afterwards the code will be manually deployed to say a pre-production environment and tested and then it is manually deployed to Production. Assume the customer says that the Specification limit for deploying all product backlog items(chosen In a Sprint) is 3-5 days (1 week Sprint).  

 

Now after some time, the team gets matured process-wise and technolgy-wise and implements DevOps pipeline and exhibits CI-CD Process Improvement. They first do the Continuos Delivery part in the CD Section. Now the automation gets extended from QA environment till the pre-production environment. This is a Process Improvement from manual to automatic. Now the customer revises the Specification limit and set the limits to <=3 days.

 

Now again the team works on the second part of CD section - Continuous Deployment. This will ensure the deployment from pre-production to Production automatic. The customer now again changes the Specification limits to <=1 day. 

 

Thus it becomes possible to change the Specification limits due to process Improvement 

 

Conclusion:
We have seen with couple of examples that how it's also possible that making Process Improvements can result in a change of Specification limits.

Process improvements do not lead to changes in specification boundaries because these boundaries are fixed and determined by the requirements of customers. However, when employing a Quality Function Deployment (QFD) model, business improvements necessitate process owners to assess how the new attributes of the product or service align with customer requirements, particularly if process improvements result in a shift in the mean of process data (e.g. call resolution times) or when measurement systems are changed (e.g. during localization processes involving unit changes). As a result, if process improvements impact product or service attributes like the mean or units of measurement, then it may be necessary for process owners to review and update the specification limits within the QFD model.

Process improvements can  lead to changes in specification limits, but this is not an absolute set rule.
 In some cases, process improvement may be initiated  to achieve better results or adapt to changing requirements, especially to extend or change specification limits.
 Here are some cases where process improvements can lead to changes in  specification limits:

Example:
If we are running any process with the As- is methodology and we find that the the data points during inspection shows that the process are lying beyond the limits.
So the plant team decides to improve the running process by means of improving the machine condition and also with some addition of Low cost automation, thereafter taking data shows that
The process are now with better tolerances and best quality, resulting in revised specification limits to reflect  improved performance.

Lets take the case of an online vendor exploring ways to improve his service level. Presently, the average duration for is 48 hours and the business looks to enhance customer satisfaction by reducing this delivery time.

 

The vendor invests in new technologies and enhancements in logistics and the updated procedure empowers the business to process and dispatch orders within 24 hours, effectively halving the processing time. 

 

As a result of this, the business decides to revise the specification limit aligning them with the recent standard. This is a typical example of how a retailer's aim to improve the service level leads to revision of specification limits.

This was a tricky one. And as expected, some of you missed the trick. Process improvements are needed when specification limits get revised, however the question was opposite. Do process improvements result in a change in specification limits?

Generally speaking, process improvements result in a change in the control limits, however there are instances where process improvements also result in a change in the specification limits. This is particularly true when the specification limits are decided by the business, R&D or market. And then there are also instances where regulators and customers play the catch up game

 

The best answer to this question is provided by R Rajesh.

 

Answers from Adil Khan, Aarti T, Keerthi Vasan are also a must read.