Toyota

The needed item reaches the next process in the needed quantity at the needed time.

How it works

Production and conveyance are synchronized to what is needed, when it is needed.

Why it is used

It reduces overproduction and inventory.

Trade-off

Lower buffers make disruption more immediately consequential.

Best fit

Relatively predictable flow with dependable suppliers.

When an abnormality occurs, equipment is stopped and the problem is made visible.

How it works

Automation is paired with human judgment to stop on abnormal conditions.

Why it is used

It prevents defects from passing downstream.

Trade-off

Stopping the line sacrifices short-term output to protect quality.

Best fit

Processes where defects can be detected at the point of work.

Continuous improvement is one of the two pillars of the Toyota Way.

How it works

People continually seek better ways of doing work.

Why it is used

It turns operational learning into an ongoing responsibility.

Trade-off

Many small changes require time, attention and stable standards.

Best fit

Operations with repeatable work and room for learning.

Before automation, work is done smoothly and correctly by hand; waste, inconsistency and unreasonable requirements are reduced, abnormalities are identified, and the learning is then built into machines.

How it works

TPS describes manual mastery, kaizen and detection as preconditions for automation rather than automating an unstable process.

Why it is used

It prevents technology from scaling poorly understood work.

Trade-off

Manual analysis delays automation investment.

Best fit

Repetitive processes where the work can be observed, standardized and instrumented.