The model lays on quite certain presumptions. There are somewhere around two firms creating a homogeneous (undifferentiated) item and can't collaborate in any capacity. Firms contend by setting costs at the same time and shoppers need to purchase everything from a firm with a lower cost (since the item is homogeneous and there are no purchaser search costs). Assuming two firms charge similar value, customers' interest is parted uniformly between them. It is least difficult to focus working on this issue of duopoly where there are only two firms, albeit the outcomes hold for quite a few firms more prominent than one