Plan-Do-Check-Act
PDCA is the basic cycle of improvement: plan with a prediction, test on a small scale, compare result with prediction, and standardise or adjust. The cycle separates learning from “let’s try something”.
A baseline number exists: you cannot see an improvement without a before
The change can be tested in a bounded way — one line, one week, one case type — before rollout
What is changed, where, over which period — and what do we expect to happen with which number? The prediction is what makes Check possible: “We expect the changeover time to fall from 45 to around 30 minutes.” Without a prediction, any outcome is “quite good”.
Carry out the change in a bounded way and be present: the deviations and surprises that arise along the way are data — not disturbances. Note them.
Measure the same number as the baseline and compare with the prediction — not just “did it get better?”, but “did it turn out as we expected — and if not, what did we misunderstand?” That question is where the learning lives.
Did it work as predicted: update the standard, train, and roll out — with the same measurement at the new places. Did it not work: adjust the hypothesis and run a new cycle. Both outcomes are progress; only the undocumented attempt is waste.
How it goes wrong in practice — and this is where most implementations part ways.
The organisation loves to plan and execute — and skips Check and Act, because the next initiative is waiting. The result is activity without accumulated learning: the same errors are made in new projects.
A PDCA over six months gives one round of learning per half-year. Four cycles of six weeks give eight times as much learning in the same calendar time.
“It feels better” is not a Check. Without a before-number, the cycle is an anecdote.
The method only works when it becomes daily routines and leadership behaviour. The operations check shows in 4 minutes where your operations stand — and what should come first.