Econ Focus

Why People Make Mistakes

While economic incentives encourage companies to invest more in workplace safety, there are other factors that can increase the likelihood of an accident on the job. James Reason, professor emeritus of psychology at the University of Manchester in Britain, has studied human error and managing the risks of organizational accidents.

In a March 2002 article in Quality & Safety in Health Care, Reason discusses why workers will forget a crucial step in a process, even if it's a routine part of the job. Here are some of the characteristics that can make a task more prone to omission:

• The task requires a lot of information that places demands on short-term memory.
• The task is functionally isolated -- that is, it isn't obviously cued by preceding actions nor follows in linear succession from them.
• The task is recursive or repeated; where two similar steps are required to achieve a particular goal, it is the second of these two steps that is most likely to be neglected.
• The task follows the achievement of the main goal of the process; such "premature exits" are due in part to the person's preoccupation with the next item on their to-do list.
• The task involves an item to be acted upon that is hidden or inconspicuous.
• The task follows an unexpected interruption; this can occur because people lose their place in the action sequence or because some unrelated action is unconsciously "counted in" as part of the task sequence.
• The task is triggered by weak, noisy, or ambiguous signals.