A PDCA cycle is not what you think it is

A PDCA cycle is assumed to be a test for countermeasure. That is one type, but there's more than one kind.

Sometimes, a PDCA cycle consists of nothing more than a quick "go & see" to confirm or deny a hypothesis, without changing or implementing anything at all.

A PDCA cycle is simply the act of taking a step forward with the intent of learning something in the pursuit of improvement.

3 Examples of PDCA Cycles

1.Go and See: Direct observation and data collection, without changing anything, to learn more about a process or situation. Of course, data collection still needs to be planned (hence the Plan step). The collection itself is the Do step. The analysis of the data is the Check phase (again, there may be planning effort to figure out how to interpret this data). The Act phase is the decision point; what insights have we gained from this data that we have collected and "checked".
2.Exploratory Experiment:  Introducing a change in a process to see, via direct observation, how the process reacts.
3.Testing a Hypothesis: Introducing a change, ideally in only a single factor, together with a prediction of what you expect to happen. This is the classic OFAT (one factor at a time) approach as opposed to DOE experiments which adjust multiple factors at the same time.

When it comes to implementing countermeasures (solutions to problems), there are also benefits in taking a PDCA or experimental/piloting approach rather than pursuing the full-scale version of the solution in one leap:

Lower Risk

•Lowers risk of failure by limiting resource usage.
•Assesses true performance in controlled-but-live experiments.

Learn

•Confirms or disproves expected results and relationships.
•Validates the benefit of the proposed solutions before roll out.
•Validates your measurement system.

Improve Solution

•Identifies additional improvements in either the solution or implementation
•Improves future projections of benefits of full roll out.

Stakeholder Relations

•Increases stake-holder buy-in.
•Quickly delivers a version of the solution to a targeted segment of the client population.