ABSTRACT
This chapter examines issues surrounding human performance at the sharp end, including those described as errors and those considered expert. It provides an introduction to the complexity of system failures and the term human error. Studies of incidents in medicine and other fields attribute most bad outcomes to a category of human performance labeled human error. For practitioners at the sharp end of the system, there are three classes of cognitive factors that govern how people form intentions to act: Knowledge factors—factors related to the knowledge that can be drawn on when solving problems in context. Attentional dynamics—factors that govern the control of attention and the management of mental workload as situations evolve and change over time. Strategic factors—the trade-offs between goals that conflict, especially when the practitioners must act under uncertainty, risk, and the pressure of limited resources.
