PDCA cycle: what it is, its 4 phases and examples of continuous improvement

The PDCA cycle, known as PHVA in Spanish, is a four-phase continuous improvement method whose phases repeat over and over: plan, do, check and act. It helps you improve a process, a product or a campaign step by step, with data and without making changes blindly.

The name PDCA cycle is an acronym for “Plan, Do, Check and Act”; in Spanish it is known as PHVA, from “Planificar, Hacer, Verificar y Actuar/Ajustar”. It is also widely known as the continuous improvement cycle or the Deming circle, and it is a process focused on continuously improving how a business is managed and run.

To do this, the four steps (Plan, Do, Check and Act/Adjust) are used as a basis and carried out cyclically to achieve continuous improvement. Once all four steps are complete, the cycle is finished and has to be repeated again, so that new improvements are regularly built into how the company or business runs.

We’ll go through what each stage of the cycle involves and, finally, give you an example so you can see in practice how to use the PDCA cycle.

The 4 phases of the PDCA cycle at a glance

Origin of the PDCA cycle

The cycle builds on the work of Walter Shewhart, who proposed an early three-step improvement cycle: specify, produce and inspect. W. Edwards Deming expanded it to four steps and presented it in Japan in the 1950s, and in 1951 the Union of Japanese Scientists and Engineers (JUSE) gave it the PDCA form we know today. That’s why it is also called the Deming circle or Deming wheel. Deming later preferred to speak of PDSA, with study instead of check.

The cycle is still very much in use today. The ISO 9001 standard recommends applying it so that processes deliver their intended results, and it is the hands-on way to carry out the Kaizen method, the philosophy of improving little by little, all the time.

Plan

At this stage, you set the objectives and goals to pursue, with a KPI to measure them, and you also identify which areas can be improved. All of this must be based on the company’s own mission, vision and values.

Do

In the Do stage, the relevant changes are implemented to achieve the objectives set. It is highly advisable to make the changes gradually to find out whether they are really beneficial before rolling them out across the board.

It consists of three basic steps: training all the employees involved in the project, implementing the project itself and, finally, analyzing the results obtained.

Check

After making the improvement, the problems and benefits it has brought are analyzed. Once these have been properly identified, if the improvement meets expectations it will be rolled out across the board; otherwise, it will be discarded or modified to bring it in line with the desired objectives.

There are two ways to verify and detect issues: in parallel with the implementation or at the end of it. The main difference is that checking in parallel lets you see whether everything is going as planned, while checking once the improvement has been implemented gives you the full set of results.

Act (Adjust)

At this stage, once the set test period is over, the results of the changes are analyzed and compared with how things worked before the changes were introduced. If the results are as desired, the improvement will be implemented permanently and on a large scale. Otherwise, corrective action must be taken to reach the desired objectives, or the improvement must be discarded altogether.

In any case, once the Act/Adjust stage is finished and the improvements have been implemented, the process returns to the planning stage, thus starting a new cycle.

PDCA cycle example

This typical PDCA cycle example will make it much clearer how the cycle is implemented. It shows the process of developing a new product to add to a company’s current catalog:

• Plan: the new product is developed and the production process it requires is defined.
• Do: in this step, a prototype (a minimum viable product) is created and tested, and the test data is analyzed.
• Check: based on the test data, a detailed analysis is made of whether the product will be viable.
• Act/Adjust: with the new design developed, the decision is made to launch the product or discard it, after which the cycle starts again.

Example of a PDCA cycle in an email campaign

Each turn of the cycle brings a small improvement, and over a year of sends they add up. For the Do phase, you can use an A/B test of the email subject line, and for the Check phase, the CTR of each version.

How Mailrelay helps

With Mailrelay you can apply the PDCA cycle to your sends without extra tools:

• A/B tests of the subject line or content for the Do phase.
• Open and click statistics on the free account and on Enterprise for the Check phase.
• Segments to test changes on part of your list.
• Free account with 80,000 emails a month and 20,000 contacts.

Frequently asked questions

What does PDCA mean?

It stands for Plan, Do, Check, Act.

What is the PHVA cycle?

It is the same PDCA cycle with the Spanish initials: planificar, hacer, verificar and actuar (plan, do, check and act).

Who created the PDCA cycle?

It builds on Walter Shewhart’s cycle. W. Edwards Deming expanded it and spread it in Japan in the 1950s, where it took the PDCA form in 1951. That’s why it is also called the Deming circle.

What is the difference between PDCA and PDSA?

They are the same cycle. Deming preferred study to check, to stress that you need to understand the results, not just verify them.

How is the PDCA cycle related to Kaizen?

Kaizen is the philosophy of improving little by little, all the time. The PDCA cycle is the method used to put it into practice.

Related entries

• Kaizen method
• A/B testing
• KPI
• Benchmarking
• SWOT analysis
• Agile marketing
• Lean startup
• Minimum viable product
• Pareto Theorem
• CTR