Deming Cycle Explained [with an example]

Deming cycle is popularly known as the PDCA cycle, and the acronym stands for Plan-Do-Check-Act. It is an iterative cycle which guarantees improvements for the activity it has been applied to.

Dr. William Edwards Deming is the man behind the concept, who is considered to be the father of modern quality control.

The PDCA Cycle

The PDCA cycle can be applied to an activity or a set of activities that are planned in advance. In the IT industry, it is mostly applied to the service management function.

The cycle is somewhat similar to Kaizen, where minor improvements are done at a time, and the cycle must be iterated to get the essence of it.

How does it Work?

Plan – Any activity you need to undertake requires some planning. The first step in the cycle is to prepare a plan which will consider all possible combinations of outcomes, risks, necessary resource requirements amongst others. I suggest you put down your plan in a word document, rather than just in your mind.

Do – As the simple two letter word says, do what you have planned.

Check – After you have done what was planned, stand back and observe. Compare the results with the plan. Analyze what else could have been done to make the output better. Document the delta and the improvements in the same word file.

Act – The analysis conducted would provide pointers on what needs to be done to fill the bridge between what was planned and what was implemented. And the improvements that were listed are implemented in this part of the cycle.

After going through the entire cycle, you need to plan for the next set of improvements, which would come in as the plan activity in the PDCA cycle. And, the iterations continue to roll, upwards.

An Example on PDCA

Plan – Let’s say you are building a website. First put down a plan on what you want to do along with rough sketches in a document. Think thoroughly on various aspects of web designing, like the features you want to include, like adding a newsletter module, a contact form and so on. Make sure that it is all in writing.

Do – Whether you outsource it to a professional or do develop the website yourself is your choice. As I said earlier, this is a very simple step. But, the do part must reproduce what the plan step states.

Check – After the website is developed. Compare the plan with what you have on hand; there will be gaps which you need to bridge in the next step. Apart from this, analyze for any improvements that can be made like adding Ajax forms instead of a normal one. Document the gaps and the improvements that you wish to make in the same document.

Act – Like the do step, perform the delta and the improvements listed in the document.

You have now completed one cycle of PDCA. Remember that this cycle is an iterative one, and you can take up as many as you want to build a website that improves every time it rolls through the cycle.

How Often to Iterate the Cycle

From experience, I have found that using one iteration after another is not feasible; if feasible, definitely not advisable.

After you complete one cycle, let the product you have on hand stabilize for a while before you take up the next cycle. I cannot recommend the period between iterations, it solely depends on your requirements, technology and personal satisfaction. But, I would never run iterations one after another.

In the website example, I would go through one cycle, and use the website for a while. Make note of all the improvements that I can make in the same document, and when the time is ripe, go through another cycle implementing the documented improvements. The time in between the cycles will allow me to reflect on what I have done, and data points for the next improvement cycle.

Let me know if you have encountered the Deming cycle earlier, if yes, did you run iterations one after another?