هم ترازی تولید و عرضه: آیا استراتژی های مختلف تولید مرتبط با شیوه های مختلف خرید است؟

Despite the recognized importance of the horizontal fit between purchasing and manufacturing, empirical research in this area is scarce. In this paper, we investigate whether different manufacturing strategies translate into different supply management practices. To do this, we develop a numerical taxonomy of manufacturing strategies based on ten competitive priorities using survey data from manufacturing plants in developed countries. Cluster analysis identifies three manufacturing strategy types: Quality customizers, Caretakers and Timekeepers. We then use analysis of variance to compare the purchasing practices of members of different manufacturing strategy groups. Results indicate that the size of the supply base and the percentage of strategic suppliers are not significantly different among the three groups. Considering the criteria for selecting suppliers, we find that Quality customizers put significantly more emphasis on all criteria, but firms in the three groups consider the same major criteria when choosing their suppliers. The adoption of coordination mechanisms with suppliers follows a similar pattern. Quality customizers show the highest level of adoption of all mechanisms, but the ranking of the level of adoption of the coordination mechanisms is similar in the three manufacturing groups. Overall, results do not show a strong link between manufacturing and purchasing strategies. Manufacturing plants in our sample do not align their manufacturing strategy with dissimilar purchasing practices. We discuss possible explanations for this unexpected result.

Researchers have long argued that strategic priorities at the functional level should be aligned with business level strategies (Ansoff, 1965 and Andrews, 1971). This vertical fit has been associated with superior firm performance and may become a source of competitive advantage (Peters and Waterman, 1982 and Porter, 1996). Researchers in Marketing, OM, HR, and IT have investigated the importance of vertical alignment between strategies and activities within their respective functional areas and the business strategy of the firm. However, as pointed out by Kathuria et al. (2007), the links between functional strategies have been overlooked. In this research, we explore the links between purchasing and manufacturing strategies. Although some attempts have been made to explore this link (Watts et al., 1992, Pagell and Krause, 2002 and Brown and Cousins, 2004), empirical research on this topic is scant (Vachon et al., 2009). In this paper, we investigate whether different manufacturing strategies translate into different supply management practices.

Our research shed some light on the links between manufacturing strategic priorities and practices in supply management. To do this, we first developed a taxonomy of manufacturing strategies and compared the results with manufacturing taxonomies reported in the literature. Cluster analysis reveals three manufacturing strategy types: Quality customizers, Caretakers and Timekeepers. Quality customizers combined the emphasis on quality of Miller and Roth's Marketeers with the emphasis on innovation of Miller and Roth's Innovators. Twenty years after Miller and Roth's taxonomy and ten years after Frohlich and Dixon's replication, Caretakers are still alive and well in developed countries, focusing almost exclusively on price. A new strategy type, Timekeepers, has emerged, putting special emphasis on fast and dependable delivery. The comparison of purchasing practices implemented by firms in each manufacturing strategy group yields interesting results. First, the size of the supply base and the percentage of strategic suppliers are not significantly different among the three manufacturing strategy groups identified. This could mean that having a limited number of suppliers and developing strategic relationships with suppliers are purchasing practices that support all manufacturing strategies. We would expect Caretakers to favor adversarial strategies vis-à-vis their suppliers to diminish the price of goods purchased and consequently have a larger supply base and put less emphasis on developing strategic relationships. Results indicate that manufacturers focused on price could also adopt collaborative strategies with their suppliers. In fact, the important variations in the results reported in the number of suppliers per item and in the percentage of strategic suppliers per cluster (Table 4) suggest that collaboration could serve manufacturers looking for innovation and quality as well as manufacturers focused on price. A similar result is reported by Vachon et al. (2009), who found that collaboration could support manufacturers that focus on lower prices. Considering the criteria for selecting suppliers, the results indicate that Quality customizers put significantly more emphasis on all criteria, suggesting that looking for quality and innovation requires selecting superior suppliers rather than focusing exclusively on price or on delivery. As showed in Table 2, Quality customizers need to surpass their competitors in several dimensions to win orders from customers. They are expected to perform simultaneously along a number of fronts, which may force them to ask for equally high performance from their strategic suppliers. Instead of accepting trade-offs when choosing their suppliers, they demand superior performance in almost all areas. If there are several significant differences in the level of importance of the criteria for selecting strategic suppliers, there are none in the order of the criteria mentioned. Firms adopting different manufacturing strategy groups focus primarily on the same four criteria when selecting their strategic suppliers: quality is the most important, followed by delivery, price, and supplier potential. The fact that firms following different manufacturing priorities use the same criteria for supplier selection is surprising. These results suggest that there is no strong consensus between manufacturing priorities and the criteria used for supplier selection. Nonetheless this internal consensus has been linked to superior performance levels (Pagell and Krause, 2002). Regarding the adoption of coordination mechanisms with suppliers, Quality customizers show the highest level of adoption, while Caretakers have the lowest. Pursuing quality and innovation simultaneously seems to require a higher level of coordination with suppliers than focusing on low cost or fast and dependable delivery. To produce high quality innovative products, Quality customizers have adopted more advanced practices to coordinate planning decisions and the flow of goods with their strategic suppliers. The analysis of the context of Quality customizers shows that they compete in a more complex environment, facing more competitors in a more open market where processes and products change more frequently (see Appendix B). Operating in a more hostile and complex context, Quality customizers are required to use more advanced supply practices than firms in the two other manufacturing groups ( Brown and Cousins, 2004 and González-Benito et al., 2010). However, similar to the criteria for selecting suppliers, the order of the adoption level of the coordination mechanisms is very similar for the three manufacturing groups. Overall, our results do not show a strong link between manufacturing and purchasing strategies. Despite the importance of this connection suggested by the literature, the manufacturing plants in our sample do not align their manufacturing priorities with different purchasing practices. We present two possible explanations for this unexpected outcome. First, the link may exist only for the best performing plants. To test this explanation, we repeat all the ANOVA analyses presented in Table 4, Table 5 and Table 6 using the top 25% firms in each cluster based on a manufacturing performance index. The results are mostly similar to those including all the firms in our sample. This first explanation is therefore not confirmed by our data. An alternative explanation could be that the purchasing practices reported in this study are best practices that can support any type of manufacturing strategy. Collaboration, focus on supplier quality, delivery, price, and supplier potential; and the adoption of coordination mechanisms with suppliers have been associated with superior manufacturing performance (Das and Narasimhan, 2000 and Vereecke and Muylle, 2006). This study suggests that this finding is true for firms that have different manufacturing priorities. 7.1. Limitations and further research This study has some limitations. First, we used single-source data. The same respondent, generally the director of operations, reported on the manufacturing and purchasing strategies of the plant. Having a different respondent for each function, such as a purchasing manager for questions related to purchasing practices, would improve the validity of the research. Additionally, the participating manufacturing plants belong to the same industry and are all located in developed countries. The explored link could be stronger in other industries or regions. We explore the link between manufacturing and purchasing strategies using a taxonomy of manufacturing strategies based on competitive priorities. However, manufacturing strategy can also be planned based on manufacturing paradigms, which include best practices and innovative manufacturing systems (Wang and Cao, 2008). To further understand the manufacturing-purchasing connection, it could be interesting to compare purchasing practices of firms using innovative manufacturing systems such as lean production and agile manufacturing (Narasimhan et al., 2006).