New to this topic?
We recommend reading these guides first to get the most out of this one:
20+
Suggestions/Person/Year (World-Class)
4
CI Maturity Levels
80%
Implementation Rate Target
Daily
Improvement Cadence

The 4-Level CI Maturity Model

LevelNameCharacteristicsImprovement Rate
1ReactiveProblems are hidden or blamed on individuals. Improvement happens only during crises. “That’s just how it is here.”0–0.5 suggestions/person/year
2Event-DrivenKaizen events happen quarterly. Improvements are made during events but backslide between them. “We do lean when the consultant comes.”1–3 suggestions/person/year
3SystematicDaily improvement cadence. Suggestion system with rapid response. Problems are welcomed because they drive learning. Leaders coach instead of direct.10–20 suggestions/person/year
4Self-ImprovingOperators drive improvement without management prompting. Standard work is updated by the people who do the work. The system improves itself.20+ suggestions/person/year

Most Western manufacturing facilities operate at Level 1–2. Toyota operates at Level 4. The gap is not tools — it is culture.

Psychological Safety: The Foundation

No improvement system works without psychological safety. If operators fear punishment for surfacing problems, they will hide problems. If supervisors fear blame for reporting misses, they will massage the numbers. If engineers fear looking incompetent for asking questions, they will make assumptions.

✅ Signals of Safety

  • Operators pull andon without hesitation
  • The Pitch Board has red blocks — and no one is punished for them
  • Supervisors say “I don’t know” and ask for help
  • Suggestions are implemented quickly and the suggester is credited
  • Mistakes are discussed as system failures, not personal failures
  • New employees are encouraged to question “why do we do it this way?”

❌ Signals of Fear

  • Operators never pull andon — “it’s not worth the hassle”
  • Pitch Boards are always green (because misses are not recorded honestly)
  • Supervisors have all the answers (because admitting ignorance is career risk)
  • Suggestions go into a box and nothing happens
  • “Who did this?” is the first question when a problem is found
  • New employees learn to keep quiet within the first week

The Suggestion System That Works

Most suggestion systems fail because they are slow (3-month review cycle), bureaucratic (committee approval required), and disconnected (the suggester never hears what happened). A system that generates 20+ suggestions per person per year has these properties:

PropertyWhat It Means
Small scopeSuggestions target the operator’s own work area. Not “redesign the factory” but “move this bin 2 feet closer to eliminate reaching.”
Fast responseTeam lead reviews within 24 hours. If it can be done in the area, implement within the week. No committee.
Implementation rate ≥80%Most suggestions are implemented. If most are rejected, people stop suggesting. Lower the bar for approval.
Visible trackingA board in the area shows: suggestions submitted, status, and who implemented them. Transparency builds trust.
Recognition, not rewardPublic thank-you, name on the board, mention in the standup. Not cash bonuses (which create gaming) but genuine recognition.

💡 The 80% Rule

If your suggestion implementation rate is below 50%, your system is generating cynicism, not improvement. Every rejected suggestion teaches the submitter “don’t bother.” Fix this by: (1) coaching people to submit smaller, more implementable ideas, (2) giving team leads authority to approve and implement without management sign-off, (3) following up with every submitter, even for rejected ideas, with a genuine explanation.

From Events to Daily Practice

The transition from Level 2 (event-driven) to Level 3 (systematic) requires shifting from periodic kaizen events to daily improvement practice:

Event-Driven (Level 2)Daily Practice (Level 3)
Improvement happens during 3–5 day kaizen eventsImprovement happens every day during normal work
Led by lean team or external facilitatorsLed by team leads and operators with coaching support
Big projects, big results, big backslideSmall experiments, small results, sustained progress
Improvement is a separate activity from workImprovement IS how work is done
5–10 improvements per year per area100+ small improvements per year per area

The mechanism for daily practice is coaching: a 15-minute daily conversation between coach and learner at the process, working on the current improvement target. Toyota Kata provides the structure.

🎯 The Bottom Line

CI culture is not about posters, slogans, or kaizen events. It is about creating conditions where every person improves every day. Psychological safety is the foundation (people must feel safe to surface problems). The suggestion system is the mechanism (small ideas, fast response, high implementation rate). Daily coaching is the cadence. And visible tracking closes the loop. Measure your culture by suggestions per person per year and implementation rate — if those numbers are low, fix the system before adding more lean tools. Next: Sustaining Gains — the systems that prevent improvement backslide.

Free forever · Every feature included

Stop reading, start modeling

Model your process flow, run simulations, optimize staffing with TOC math, and test your knowledge with 107 interactive checks — all in one platform.

Open Workbench →

Take this to a room

The running order

For leadership measuring culture. They should leave with two numbers to track: suggestions per person per year and implementation rate.

7 beats · 12 min
  1. 1

    Measure the culture with two numbers

    Culture feels unmeasurable until you pick these two, and then it stops being an opinion.

    • Suggestions per person per year. World class is 20 or more.
    • Implementation rate. Target 80 per cent.
    • If those numbers are low, fix the system before adding any more lean tools.

    Ask the room What are our two numbers?

  2. 2

    The 80 per cent rule

    Below 50 per cent implementation, your suggestion system is manufacturing cynicism.

    • Every rejected suggestion teaches the submitter not to bother.
    • Three fixes: coach people to submit smaller, implementable ideas.
    • Give team leads authority to approve and implement without management sign-off.
    • Follow up with every submitter, including rejections, with a reason.
  3. 3

    Small ideas, fast response

    The system design that produces high numbers is the opposite of what most plants build.

    • A suggestion scheme that routes through three approvals will get a handful of ideas a year.
    • Small ideas implemented this week beat big ideas evaluated next quarter.
    • The target is many small improvements, not a few large ones.
  4. 4

    Psychological safety is the foundation

    None of the mechanism works if people do not feel safe surfacing a problem.

    • The leader's reaction in the first five seconds is the entire policy.
    • Leaders who never say I do not know create teams that never say it either.
    • Celebrate the person who found the problem, not only the one who fixed it.

    Ask the room When did someone last tell us something we did not want to hear?

  5. 5

    Four levels of maturity

    Knowing where you are stops you deploying a level-four practice into a level-one culture.

    • 1: compliance - people improve when told.
    • 2: participation - people join events when invited.
    • 3: ownership - people improve their own work without being asked.
    • 4: culture - improvement is how the work is done, continuously.
  6. 6

    From events to daily practice

    Kaizen events are a level-two mechanism. Daily improvement is level three.

    • Events make a big change in a week. They do not build a habit.
    • A plant that only improves during events improves about five days a year.
    • The transition from events to daily practice is the actual maturity step.

    Ask the room How many improvements happened here last week outside an event?

  7. 7

    Close every loop, visibly

    Tracking is what proves the system is real, and visible tracking is what makes it believed.

    • Post submissions, implementations and the rate.
    • Follow up with every submitter, even for a no.
    • Culture is not posters or slogans. It is whether an idea gets a response.

    Ask the room Who owns the response, and within how many days?