Examples of the need for Human Factors

People have a conceptual model of how they expect a system to work, based on prior experience with similar systems. When something does not work as expected, mistakes can occur or less reliable processes may be undertaken that the designers did not account for. Errors in a system can also be the result of poor design, such as a complex user interface or using iconography on buttons that do not easily portray the intended action. The following examples are medical devices that reached market without sufficient human factors input. In some cases, they had not been properly tested resulting in the loss of life; in others, the impact that the medical device would have on the surgical team was not discovered until used in practice.