They must know when parts will be needed so the order can be placed in time. If the parts are missing, many businesses have to stop production. Buyers often are not told what to buy. Instead, they buy what they think will appeal to customers. Thus buyers must be aware of the latest fashion trends.
Buyers also watch their competitors and see what they are buying.
Buyers and purchasers often specialize in what they buy. For example, a buyer for a department store may buy only childrens clothing. A purchasing agent for a wood products company may buy only one type of wood. In small companies, however, one buyer may buy all the products. Buyers and purchasers keep track of economic information that relates to their product.