Action Slip

An action slip is an everyday error in carrying out a well-practiced, largely automatic sequence of actions, in which a person's actual behavior diverges from what they clearly intended to do, even though they possess adequate knowledge and skill to perform the task correctly, such as absent-mindedly pouring orange juice into a bowl set out for cereal, or heading toward a former workplace instead of a new one out of sheer habit. The psychologist James Reason developed an influential and widely cited taxonomy of such slips in his 1990 book Human Error, distinguishing them from mistakes, which he defined as errors arising from a faulty plan or intention in the first place, since a slip specifically involves a correctly formed intention that then goes wrong somewhere in its execution. Reason's framework identifies several recurring patterns behind action slips, including capture errors, in which a more familiar, habitual action sequence takes over partway through an intended but less practiced one, and description errors, in which an intended action is directed at the wrong object because that object shares enough features with the correct target to trigger the wrong routine. Action slips are understood to occur especially often when attention is divided or distracted during the execution of a task that has become so well learned it can normally run with little conscious monitoring, since it is exactly that reduced monitoring that allows a habitual but unintended action sequence to run to completion unchecked.