Why doesn't Erbert and Gerbert set up separate systems for each type of sandwich, e$.$g$.$ one system for making only the Boney Billy sandwiches, a separate system for making only the Comet Morehouse, a separate system for making only the Jacob Bluefinger, and a separate system for every other type of sandwich on the menu? $($Check all that apply$)$

The processing requirements for the different sandwiches are sufficiently similar, so they can easily share the same resources without major reconfiguration of equipment between sandwich varieties

No single sandwich has sufficient demand volume to justify dedicated resources used only to make that one type of sandwich