This single finished product bill of material is perfectly suitable as long as the company sells only 220 V 50 mm diameter flow meters.
On the other hand, as soon as the firm wishes to diversify its production by proposing a variety of diameters and different voltages, it has to create as many bills of material as there are assembled finished products (for example, with 10 diameters and three voltages, the number of finished products goes up to 30 } at kitchen manufacturers, one can find up to several thousand finished products). Using classical MRP2 logic, it becomes heavy to manage so many bills of material and forecasts.
The goal of assembly planification is to identify different sequential variants for the course of assembly operations and to evaluate these variants so as to determine the optimal sequences. To do that, the optimization criterion is the minimum cost of the entire process.