In psychological and economical sciences, irrationalities of customers in making decisions at the point of sale is a research topic for several years. A lot of phenomena were observed and analyzed, which do not fit to the approach that humans behave as homines economici. Marketing approaches take advantage of those irrationalities to increase the products’ sales for example by a special product presentation. Traditional design approaches do not regard irrationalities of customers in product design. In this paper, we present the results of a literature study, where several irrational customer choices (ICC) at the point of sales (POS) were identified. Furthermore, the causes and underlying theories are outlined. We conclude with the need to integrate irrationality of customers also beyond POS into product design to increase products’ sales.     «

In psychological and economical sciences, irrationalities of customers in making decisions at the point of sale is a research topic for several years. A lot of phenomena were observed and analyzed, which do not fit to the approach that humans behave as homines economici. Marketing approaches take advantage of those irrationalities to increase the products’ sales for example by a special product presentation. Traditional design approaches do not regard irrationalities of customers in product desi...     »