Measurement
You have the cycle times. Now what does the picture mean?
A histogram of how long things take has four things in it worth acting on, and the average is not one of them. What to look for, and what each shape is telling you.
What if
How do I test a process change without running the experiment on customers?
The three ways to find out what a change will do before committing to it, what each costs, and the point at which arithmetic on paper stops being enough.
Queueing
Every step has an owner. The waiting between them has none.
Process owners are assigned to the boxes. Most of the elapsed time is in the arrows, and an arrow with no owner is time nobody is accountable for or measuring.
Line balance
Our demand swings by half. Does takt time still apply?
Takt assumes steady demand and almost nobody has it. The answer is not to abandon it, and it is not to average the year. It is to pick the window you are willing to be wrong in.
Constraints
We fixed the bottleneck and the output barely moved
A constraint that is relieved does not disappear, it relocates. Knowing where it goes next is the difference between one improvement and a program of them.
More pieces
Batching
Most of your changeover happens while the machine is stopped for no reason
Measurement
We have no data. Where do we start?
Flow
Moving to pull does not remove the inventory. It shows you where it was.
Queueing
How long will this backlog take to clear? There is an equation for that
Process mapping
Ninety seven percent of that form's life is waiting
Variation
Your step does not take eight minutes. It takes a shape.
Scheduling
Monday looks worse because Friday never finished
Root cause
The five whys finds one cause, and most delays do not have one
Constraints
We added two people and nothing came out any faster
Quality
A ten percent rework rate is not a ten percent problem
Process mapping
The boxes on a process map are not where the time goes
Standard work
You cannot automate a step that is done five different ways
Variation
The average was met and a quarter of the orders were late
Bottlenecks
The hour you lost at the bottleneck did not cost forty five dollars
Batching
A batch size is a changeover time that nobody measured
Utilization
The last ten percent of utilization costs more than the first eighty
Queueing
Little's Law does not care what the board says
Measurement
Cycle time and lead time are not the same number
Line balance
Takt time is a demand number, not a target
Constraints
Most constraints get elevated before they are ever exploited
The paper
Three pieces a week, each one built around a calculation the reader can reproduce. Nothing is asserted here that was not checked, and no piece ends in a pitch.
Fundamentals
The ideas the rest of it is built on, worked properly rather than defined and left there.
6 pieces
Metrics and maths
The measures that get quoted in meetings, what each one actually counts, and the arithmetic behind them.
8 pieces
Lean tools
Shop floor method: what each tool is for, and the conditions it needs to work at all.
6 pieces
Case walkthroughs
One process, followed end to end, with every number shown along the way.
2 pieces
Simulation and what if
Asking a question about a process before changing it, and knowing what the answer is worth.
3 pieces