Production system
Makes and delivers products & services
while developing craftsmen
while developing craftsmen
Standards & methods
Standards & methods define the work
Standardized work defines the sequence, timing, and quality checks for every task. It is the baseline against which any deviation becomes visible. Without it, there is nothing to detect — and nothing to demand a response from the management system.
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Flow
Flow of material & information
In lean production, material and information move in sync — ideally one piece at a time, at the pace of customer demand (takt time). When flow is disrupted, the stoppage is immediate and visible. Flow is where the value is created and where the waste hides.
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Detection
Deviations detected (andon)
The andon is the nervous system of the production system. Any worker can signal a deviation — a defect, a delay, a safety concern — and the system stops and responds. In a well-tuned system, hundreds of these signals fire every day. Each one is a unit of demand for the management system.
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Generates demand
(problems requiring countermeasures)
Green
No demand
The system is running to standard. No deviation has been detected, so no demand is generated for the management system. The system is active — but not producing countermeasures. This is the steady state.
Red
Demand signal
Management system
Makes and delivers countermeasures
while developing problem solvers
while developing problem solvers
Triage
Signal, sort, disseminate, escalate
The first job of the management system is to receive and route the signal. Not every problem needs the same response — some are resolved by the nearest team leader in seconds, others need cross-functional escalation. Getting this sort right is what separates a responsive system from a reactive one.
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Diagnosis
Organize, diagnose, facilitate
Once the right people are assembled, the management system helps them understand the problem clearly — go to the actual place, observe the actual situation, map the gap between what is and what should be. The manager's role here is facilitator, not fixer.
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Resolution
Counter-measure & close
A countermeasure addresses the root cause and closes the gap — then gets confirmed to have worked. It is not the same as a quick fix that suppresses the symptom. Closing the loop (the "Check" and "Act" in PDCA) is what builds organizational learning.
Respond as close to real time
as the work demands.
as the work demands.
real-time response
Differentiated capacity
Type 1 (90%)
Team leaders, real-time
About 90% of problems are Type 1 — deviations from standard that a trained team leader can resolve at the source, in real time. This is why Toyota maintains a ratio of one team leader per 4–6 members: that ratio provides enough capacity to handle the volume of Type 1 problems without letting them linger.
Type 2–3
Huddles, A3, cross-functional
Recurring gaps (Type 2) and improvement toward new performance targets (Type 3) require more time, more people, and structured methods. Daily huddles, weekly reviews, A3 problem-solving, and cross-functional participation create the dedicated capacity for these problems.
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