Often when prices are too high and demand for a product or service lessens, it is because consumers have found a suitable substitute. Substitution happens all the time as a result of economic decisions that are made by consumers. For example, if someone needs a winter coat and likes one with a designer name and a price that reflects that name, the purchase may not be made. Instead, the person finds a similar coat that does not have a designer label and purchases it instead at a much lower cost.
For a given market of a commodity, demand shows the quantity that ...