Wednesday, December 5, 2012

Drift Into Failure by Sydney Dekker

Sydney Dekker's Drift Into Failure* is a noteworthy effort to provide new insights into how accidents and other bad outcomes occur in large organizations. He begins by describing two competing world views, the essentially mechanical view of the world spawned by Newton and Descartes (among others), and a view based on complexity in socio-technical organizations and a systems approach. He shows how each world view biases the search for the “truth” behind how accidents and incidents occur.

Newtonian-Cartesian (N-C) Vision

Issac Newton and Rene Descartes were leading thinkers during the dawn of the Age of Reason. Newton used the language of mathematics to describe the world while Descartes relied on the inner process of reason. Both believed there was a single reality that could be investigated, understood and explained through careful analysis and thought—complete knowledge was possible if investigators looked long and hard enough. The assumptions and rules that started with them, and were extended by others over time, have been passed on and most of us accept them, uncritically, as common sense, the most effective way to look at the world.

The N-C world is ruled by invariant cause-and-effect; it is, in fact, a machine. If something bad happens, then there was a unique cause or set of causes. Investigators search for these broken components, which could be physical or human. It is assumed that a clear line exists between the broken part(s) and the overall behavior of the system. The explicit assumption of determinism leads to an implicit assumption of time reversibility—because system performance can be predicted from time A if we know the starting conditions and the functional relationships of all components, then we can start from a later time B (the bad outcome) and work back to the true causes. (p. 84) Root cause analysis and criminal investigations are steeped in this world view.

In this view, decision makers are expected to be rational people who “make decisions by systematically and consciously weighing all possible outcomes along all relevant criteria.” (p. 3) Bad outcomes are caused by incompetent or worse, corrupt decision makers. Fixes include more communications, training, procedures, supervision, exhortations to try harder and criminal charges.

Dekker credits Newton et al for giving man the wherewithal to probe Nature's secrets and build amazing machines. However, Newtonian-Cartesian vision is not the only way to view the world, especially the world of complex, socio-technical systems. For that a new model, with different concepts and operating principles, is required.

The Complex System

Characteristics

The sheer number of parts does not make a system complex, only complicated. A truly complex system is open (it interacts with its environment), has components that act locally and don't know the full effects of their actions, is constantly making decisions to maintain performance and adapt to changing circumstances, and has non-linear interactions (small events can cause large results) because of multipliers and feedback loops. Complexity is a result of the ever-changing relationships between components. (pp.138-144)

Adding to the myriad information confronting a manager or observer, system performance is often optimized at the edge of chaos, where competitors are perpetually vying for relative advantage at an affordable cost.** The system is constantly balancing its efforts between exploration (which will definitely incur costs but may lead to new advantages) and exploitation (which reaps benefits of current advantages but will likely dissipate over time). (pp. 164-165)

The most important feature of a complex system is that it adapts to its environment over time in order to survive. And its environment is characterized by resource scarcity and competition. There is continuous pressure to maintain production and increase efficiency (and their visible artifacts: output, costs, profits, market share, etc) and less visible outputs, e.g., safety, will receive less attention. After all, “Though safety is a (stated) priority, operational systems do not exist to be safe. They exist to provide a service or product . . . .” (p. 99) And the cumulative effect of multiple adaptive decisions can be an erosion of safety margins and a changed response of the entire system. Such responses may be beneficial or harmful—a drift into failure.

Drift by a complex system exhibits several characteristics. First, as mentioned above, it is driven by environmental factors. Second, drift occurs in small steps so changes can be hardly noticed, and even applauded if they result in local performance improvement; “. . . successful outcomes keep giving the impression that risk is under control” (p. 106) as a series of small decisions whittle away at safety margins. Third, these complex systems contain unruly technology (think deepwater drilling) where uncertainties exist about how the technology may be ultimately deployed and how it may fail. Fourth, there is significant interaction with a key environmental player, the regulator, and regulatory capture can occur, resulting in toothless oversight.

“Drifting into failure is not so much about breakdowns or malfunctioning of components, as it is about an organization not adapting effectively to cope with the complexity of its own structure and environment.” (p. 121) Drift and occasionally accidents occur because of ordinary system functioning, normal people going about their regular activities making ordinary decisions “against a background of uncertain technology and imperfect information.” Accidents, like safety, can be viewed as an emergent system property, i.e., they are the result of system relationships but cannot be predicted by examining any particular system component.

Managers' roles

Managers should not try to transform complex organizations into merely complicated ones, even if it's possible. Complexity is necessary for long-term survival as it maximizes organizational adaptability. The question is how to manage in a complex system. One key is increasing the diversity of personnel in the organization. More diversity means less group think and more creativity and greater capacity for adaptation. In practice, this means validation of minority opinions and encouragement of dissent, reflecting on the small decisions as they are made, stopping to ponder why some technical feature or process is not working exactly as expected and creating slack to reduce the chances of small events snowballing into large failures. With proper guidance, organizations can drift their way to success.

Accountability

Amoral and criminal behavior certainly exist in large organizations but bad outcomes can also result from normal system functioning. That's why the search for culprits (bad actors or broken parts) may not always be appropriate or adequate. This is a point Dekker has explored before, in Just Culture (briefly reviewed here) where he suggests using accountability as a means to understand the system-based contributors to failure and resolve those contributors in a manner that will avoid recurrence.

Application to Nuclear Safety Culture

A commercial nuclear power plant or fleet is probably not a complete complex system. It interacts with environmental factors but in limited ways; it's certainly not directly exposed to the Wild West competition of say, the cell phone industry. Group think and normalization of deviance*** is a constant threat. The technology is reasonably well-understood but changes, e.g., uprates based on more software-intensive instrumentation and control, may be invisibly sanding away safety margin. Both the industry and the regulator would deny regulatory capture has occurred but an outside observer may think the relationship is a little too cozy. Overall, the fit is sufficiently good that students of safety culture should pay close attention to Dekker's observations.

In contrast, the Hanford Waste Treatment Plant (Vit Plant) is almost certainly a complex system and this book should be required reading for all managers in that program.

Conclusion

Drift Into Failure is not a quick read. Dekker spends a lot of time developing his theory, then circling back to further explain it or emphasize individual pieces. He reviews incidents (airplane crashes, a medical error resulting in patient death, software problems, public water supply contamination) and descriptions of organization evolution (NASA, international drug smuggling, “conflict minerals” in Africa, drilling for oil, terrorist tactics, Enron) to illustrate how his approach results in broader and arguably more meaningful insights than the reports of official investigations. Standing on the shoulders of others, especially Diane Vaughan, Dekker gives us a rich model for what might be called the “banality of normalization of deviance.” 


* S. Dekker, Drift Into Failure: From Hunting Broken Components to Understanding Complex Systems (Burlington VT: Ashgate 2011).

** See our Sept. 4, 2012 post onCynefin for another description of how the decisions an organization faces can suddenly slip from the Simple space to the Chaotic space.

*** We have posted many times about normalization of deviance, the corrosive organizational process by which the yesterday's “unacceptable” becomes today's “good enough.”

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