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Total quality management (TQM) has become accepted practice in services. Concepts from TQM in manufacturing, such as benchmarking, diagnostic tools (fishbone diagrams, Pareto charts, and so on), and customer-driven design (through quality function deployment), have joined with such concepts as service guarantees and service recovery planning to drive the quality philosophies of many service firms. Nevertheless, there remains the monumental challenge of quality assurance when the goal is to achieve zero defects in the day-to-day provision of services. Our objective here is to suggest how another concept with proven success in manufacturing, fail-safing, can and should be applied systematically to services to achieve this goal.1
The Nature of Fail-Safing
The idea of fail-safing is to prevent the inevitable mistake from turning into a defect. The late Shigeo Shingo (known as “Mr. Improvement” in Japan) articulated this basic concept. In his writings, Shingo gave examples of how manufacturing companies have set up their equipment and manual processes to prevent errors in parts counts, sequence of work performance, and product configurations. Shingo’s concepts are seen as particularly appropriate where full-scale automation is too costly or is otherwise impractical. According to Hall, “Simple fail-safe methods are the low-cost route to parts-per-million error rates.”2
The objective of fail-safing is similar to what Taguchi methods have attempted in creating robust products and processes — that is, ensuring that they can withstand the effects of factors beyond the producer’s control. We see two main differences between fail-safing and these methods. The first is the relative complexity of Taguchi methods compared to fail-safing: Taguchi methods rely heavily on sophisticated statistical techniques to set optimal product and process parameters. Fail-safing, by contrast, does not require that a specific value be put on process parameters. It requires only the ability to discriminate good from bad. As such, it is easier to apply to intangible service processes.
The second difference is more subtle, concerning the strategy taken by each approach in controlling the process. As mentioned, Taguchi methods strive to make the product or process resistant to factors beyond its control. Fail-safing, instead, governs factors within the producer’s control and then strives to extend the scope of the control to outside factors.
Poka-Yokes as Mistake-Proofing
Central to Shingo’s approach are inspection and poka-yokes (automatic devices or methods). Shingo defines three categories of inspection, all of which should be done at the 100 percent level.
1. We believe that fail-safing has decided advantages over the other logical choice for service process control, statistical process control (SPC). This is due to the humanistic nature of services, which makes them particularly prone to human error. As a statistical method, SPC is designed to ignore random variation and signal statistically significant events. Human error is, however, a random event and thus will be ignored by SPC. (In SPC terminology, human error will become part of the common cause variation.) Therefore, if SPC cannot detect human error, then it will not be able to control its effect on the service process.
2. R. Hall, Attaining Manufacturing Excellence (Homewood, Illinois: Dow Jones-Irwin, 1987).
3. S. Shingo, Zero Quality Control: Source Inspection and the Poka-yoke System, trans. A.P. Dillon (Cambridge Massachusetts: Productivity Press, 1986).
4. A.G. Robinson and D.M. Schroeder, “The Limited Role of Statistical Quality Control in a Zero Defect Environment,” Production and Inventory Management Journal 31 (1990): 60–65.
5. T. Levitt, “Production-line Approach to Service,” Harvard Business Review, September-October 1972, pp. 41–52. Levitt reveals how, to keep its surrounding property clean, McDonald’s placed numerous conspicuously colored trash cans throughout the parking lots. The assumption was that customers would not litter while looking at an obvious trash can only steps away.
6. A. Parasuraman, B. Zeithaml, and L. Berry, “SERVQUAL: A Multiple-Item Scale for Measuring Customer Perceptions of Service Quality,” Journal of Retailing, Spring 1988, pp. 12–40.
7. SERVQUAL is primarily a measurement tool, and, although its dimensions represent important aspects of the service in the eyes of the customer, they do not directly relate to the activities of the server. This is because the SERVQUAL dimensions were obtained by disaggregating a perceptual construct, service quality, into factors that best explained different perceived levels of quality, rather than by grouping the fundamental observed components of the service delivery system into larger more homogenous categories.
8. K. Anderson and R. Zemke, Delivering Knock Your Socks Off Services (New York: AMACOM, 1991).
9. C. Sewell and P.B. Brown, Customers for Life (New York: Doubleday, 1990).
10. F. Luthans and T. Davis, “Applying Behavioral Management Techniques in Service Organizations,” Service Management Effectiveness, ed. D. Bowen et al. (San Francisco: Jossey-Bass, 1990), pp. 177–209.
11. R.E. Yates, “Lawyers not Exempt from Quality Crusade,” Recrafting America (Chicago: Chicago Tribune Company, 1991).
12. J. Edelson, “The Food Service Industry: Examples in Products and Services” (Los Angeles: University of Southern California, Failsafe Project Report, June 1989).
13. Andersen and Zemke (1991).
14. R. Caplan, Why There Are No Locks on the Bathroom Doors in Hotel Louis XIV and Other Object Lessons (New York: McGraw-Hill, 1984).
15. J. Kingman-Brundage, “The ABCs of Service System Blueprinting,” Designing a Winning Service Strategy, ed. M.J. Bitner and L.A. Crosby (Chicago: American Marketing Association, 1989).
16. Sewell and Brown (1990).
17. Nikkan Kogyo Shimbun/Factory Magazine, ed., Poka-Yoke: Improving Product Quality by Preventing Defects (Cambridge, Massachusetts: Productivity Press, 1988), p. 100.
18. Sewell and Brown (1990).
20. Services could benefit from a compendium of poka-yoke examples similar to those compiled for manufacturing in:
Nikkan Kogyo Shimbun/Factory Magazine (1988).