In a recent video, the director of operations, Mr. Stankovic, explains how cameras are assembled in the current workflow in the Wetzlar buildings. To give you some context, the classical way of manufacturing, serial numbers allocation and assembly may be elucidated.
When Leica had only two camera systems (the R- and M-line) with a range of lenses, the workflow was like this: the product manager decided how many cameras and lenses were to be made, based on demand and sales forecasts. Then for every camera and lens a batch of serial numbers was reserved and the production of such a batch started. The production of every batch required time, because the batches were made in succession. This had the consequence that some products were temporarily unavailable or (worse!) did not sell at all and were in stock for a long time. This method was transparent, but had the danger that capital was destroyed. The manufacturing method was a version of the very old assembly line: a line of workstations was established and on every workstation one person assembled some parts of the product.
The agility concept implies that the production responds very quickly, if not immediately to market movements. A new product requires a fast production run to have enough items available, but the demand of existing products also needs to be satisfied. Therefore the new method is to have a number of assembly stations where one person assemblies up to ten different products (presumably in a period between a day and a week). This method explains a few things: serial numbers are now almost allocated at random, the product quality is less than what it was. Classical cameras (like the M-A) are organically assembled from a number of parts. That is why one person on one workstation assembles one camera at a time. This can be done because demand is low.
Modern digital cameras are assembled with subgroups (like shutter mechanism and electronic boards) and every assembly stage is controlled by computer. This makes it easier to assemble a variety of products in a short period. For lenses the same method is implemented.
The advantages are clear: hardly any obsolete stock and a fast reaction to changing demands. The disadvantage? Think for yourself!