The warehouse has a shelf for the things you buy rather than print — magnets, keyrings, boxes, bags. Each one carries what it cost you, what you charge for it and how many are left, and a delivery is booked in by saying how many arrived instead of retyping the total.
A print model can say which of those parts it needs, and an order picks them off the shelf. The count comes down when the job starts printing, and a job there are not enough parts for says which part before it starts. Cancelling asks the one question only you can answer: magnets still in their bag go back on the shelf, a box already taped shut does not.
Parts are added to the price after the markup rather than through it. That was the point of all of it: four magnets in a job used to mean raising the price by hand, which recomputed the margin and made a job charged 2.2x read in the reports as if it were charged four times over.
The quick calculator now shows what one piece costs to make beside what one sells for.
A list's filter box no longer makes the browser offer to fill in your password over the list you were trying to read.