Rate of Growth The product population curve shows the actual population of the product within the market at any given time. So the slope of the curve shows the rate at which the market population of the product is increasing at any given time.

In other words, the slope of the curve is the rate at which the market is consuming the product (in units per day). It is also, by default, also the rate at which the product is produced and sold (also in units per day).

By plotting another graph showing how the slope of the product population graph rises and falls, we get a curve showing the rise and fall in the rate of consumption (and hence the rate of production required to meet that consumption). This curve is shown below.

This curve however shows only the part of the rate of production which causes the market population of the product to grow initially. However, after a time, the product units which are already out there in the market start to wear out and need replacing. Therefore another smaller element of production is required by the market to replace old product units as they wear out and die.

The product death rate is proportional to the actual product population. The death rate curve is therefore a smaller version of the original population growth curve off-set to the right. Adding the production required to compensate for the product's death rate to the production required to meet initial population growth we get a curve which rises to a very high initial peak and then sinks back again to a low constant demand.

Demand for the product after the market has reached saturation can be improved by shortening the product's life-span (ie: the length of service it gives before wearing out) and also by making it non-repairable. The quicker it wears out, the sooner the consumer has to buy a new one. This raises the level at which the curve finally flattens out.

In a technology-driven competitive market, other enterprises will soon produce a 'better' product which will render the original one obsolete or push it out of fashion. So the demand for the original product falls and finally sinks back to zero. So also does its price.

The capitalist's enterprise therefore has to be established and expanded very quickly at first to meet this initial peak demand. It needs to take on lots of labour. It needs to acquire large premises. It needs to buy lots of machinery and raw materials. Then, when this initial peak demand falls, it must shed most of the labour it took on. It must get rid of most of the premises it acquired. It must sell off most of the machinery it bought. Its production must fall. And so must the capitalist's income. This is not good. The capitalist must find ways of maintaining market consumption at the highest possible level so that both his enterprise, and the income with which it provides him, remain as large and as constant as possible.