Production flow · The flow map · Element
The queues
Where work waits between operations, and how much waits there.
The part
What it is
Queue size is directly observable by walking the floor, which makes it the easiest thing on the map to measure and the most often omitted.
A queue is inventory, and it carries all the cost of inventory plus the delay it causes.
The smallest level
The attributes it carries
Each attribute is one of the framework’s shared types. What a date is, and how it is written, is defined once for the whole model — the note here says what it means in this particular place.