Method

Continuous improvement

In French: Kaizen (amélioration continue)

Kaizen is continuous improvement in small steps, led by those who do the work, as opposed to breakthroughs driven from outside.

What it is

Kai (change) and zen (good): change for the better. Kaizen refers to improvement obtained through a succession of small steps, decided and implemented by the teams themselves, rather than by a top-down project.

It rests on the PDCA cycle — Plan, Do, Check, Act — popularised by W. Edwards Deming. The decisive point of the cycle is the Check: without verification of the effect obtained, continuous improvement is only a succession of changes.

Kaizen is distinguished from kaikaku, breakthrough transformation. Both are necessary and neither replaces the other: the breakthrough creates a new level of performance, kaizen prevents it from being lost.

Kaizen event

The short format — often three to five days, with a cross-functional team mobilised full time on a narrow scope — is effective when the problem is circumscribed and the decision can be taken on the spot.

It becomes counterproductive when it serves as a substitute for the daily work of improvement: an organisation that improves only during its events regresses between two of them.

Why the standard comes first

An improvement holds only if the previous state was defined. Without a written standard, everyone works their own way: you do not know what you changed, you cannot measure the effect, and practice returns to its starting point as soon as attention moves elsewhere. That is Taiichi Ohno’s formula — where there is no standard, there can be no kaizen.

The standard is therefore not the enemy of continuous improvement, it is its condition. And it is made to be replaced: a standard that has not moved in three years signals improvement at a standstill, not a process under control.

Practical corollary: the first deliverable of a successful kaizen is not the gain, it is the new standard. If it is not written before the team disperses, it will not be.

The common mistake

Counting ideas rather than effects. An indicator of the "number of suggestions per person per year" kind produces exactly what is measured: suggestions. Measuring the performance gap obtained, even on few actions, completely changes what the teams propose.

On the shop floor — Healthcare

In a hospital ward, the improvements that held were those decided by the nursing staff themselves on the organisation of their care trolley. Those designed by an outside working group, better argued on paper, disappeared within a few weeks.

The other tools illustrated by this trade: healthcare and life sciences.

Frequently asked questions

What does the word kaizen mean?

It joins two Japanese characters, one for change, the other for good: literally, changing for the better. In industrial usage, it refers to improvement obtained through a series of small-scale adjustments, decided and applied by the teams who do the work, rather than a programme designed elsewhere and handed down.

What is the difference between kaizen and kaikaku?

One advances through frequent, small-scale adjustments, the other through the abrupt transformation of a process or a piece of equipment. They are not substitutes for each other: the transformation sets a new performance level, the successive adjustments prevent it from being lost again once attention has moved elsewhere.

How long does a kaizen event last?

The usual format occupies a cross-functional team full time for three to five days, on a deliberately narrow subject. That duration is in no way prescriptive: it corresponds to the time during which operational staff can be released without disrupting their activity, and to a scope small enough to be dealt with entirely before they return.