What is Kaizen: origin and philosophy of continuous improvement

In one line

Kaizen is continuous, incremental improvement done by the people who do the work, not a big overhaul decided at the top and handed down by decree.

What it is

"Kaizen" comes from the Japanese kai (change) and zen (good): change for the better. The word became popular in the West through the postwar Japanese automotive industry, but the underlying idea is simple: instead of waiting for a big investment to solve a problem, you attack it with small, cheap changes that are quick to test, made by those who know the process first-hand.

INTI describes it as a work philosophy rather than a specific technique: it rests on the idea that nobody knows a workstation better than the person who occupies it every day, and that this person can (and should) propose improvements to their own process.

What it is for

In a plant, Kaizen is used to reduce waste (time, movements, materials, waiting) without waiting for the next long shutdown or the next investment budget. In maintenance in particular, it helps tackle chronic problems of low severity but high frequency — the ones that are never a priority on a list of critical failures but add up to lost hours all year: a poorly labeled panel, a tool that is never where it should be, a preventive checklist that gets filled in badly because the format is confusing.

How it is applied: the Kaizen event

The Kaizen Institute formalizes this in the "Kaizen event": a small, multidisciplinary team dedicates a limited number of days (typically 3 to 5) to mapping a specific process, identifying waste, testing a change and leaving it working before disbanding. The typical structure is:

1. Define the problem and the scope (narrow, not "fix all of maintenance")
2. Observe the real process where it happens (gemba), not in a meeting
3. Identify waste: waiting, transport, rework, badly located spare-parts inventory
4. Propose and test simple, low-cost countermeasures
5. Standardize what worked (procedure, checklist, signage) so it is not lost over time

Benefits

• Visible changes in days, not months — it sustains the team's motivation
• It does not depend on approval of a large investment
• The improvement is designed by the person who will live with it, so it is more likely to last
• It builds the habit of questioning "that's how it has always been done" instead of accepting it

Limitations to keep in mind

• Kaizen does not replace the redesign of a process that is broken at the root: it is for polishing, not for fixing a structural problem (that takes a bigger project, or even a redesign with RCM)
• If what worked is not standardized, the improvement fades within a few weeks
• A poorly focused Kaizen event (scope that is too ambitious) tends not to close within the allotted time and loses credibility

In summary

Kaizen is the philosophy of improving in small, consecutive steps, made by the people in the process — not a one-off project. Its typical unit of work is the Kaizen event: bounded, with direct observation on site, and with a standardized change at the end. In maintenance it is the natural tool for the chronic low-severity waste that no criticality-based priority list will tackle on its own.