Supplier Dependency and Supply Chain Resilience

Introduction

Supply chain disruption represents one of the most significant operational risks faced by manufacturing organisations in the contemporary global economy. The COVID-19 pandemic demonstrated with unusual clarity the fragility of supply networks optimised for efficiency rather than resilience. This analysis examines the supply chain vulnerability of a mid-sized electronics manufacturer, Company X, through the application of Resource Dependence Theory (Alkhuzaim, Kouhizaim and Sarkis, 2022) and simulation modelling, arguing that the primary vulnerability is the company's structural dependence on a single tier-one supplier for a critical component and that the evidence supports dual sourcing as the primary mitigation recommendation.

Resource Dependence Theory and Supply Risk

Resource Dependence Theory, as formulated by Pfeffer and Salancik (1978) and extended in the supply chain context by Alkhuzaim, Kouhizaim and Sarkis (2022), provides a theoretical framework for understanding how organisations become strategically vulnerable when they depend on external sources for critical resources over which they have limited control. The theory predicts that dependence on a single supplier for a critical input creates asymmetric power relations that expose the dependent organisation to disruption risk, price manipulation, and strategic opportunism. In the case of Company X, the critical resource is a microcontroller component that accounts for approximately 40 per cent of the bill of materials cost for the company's primary product line. Eighty per cent of the company's supply of this component is sourced from a single tier-one supplier, with no alternative source contractually engaged. This configuration satisfies all three conditions for high resource dependence in Alkhuzaim et al.'s (2022) framework: the component is critical; the supplying market is concentrated, with only three global manufacturers capable of producing the component to the required specification; and the company has made no investments in supply chain diversification that would reduce its dependence.

Simulation Evidence

The theoretical assessment of vulnerability is quantified through discrete event simulation, which models the supply chain under a range of disruption scenarios. The simulation was constructed using historical demand data, supplier lead time distributions derived from purchasing records, and disruption duration scenarios informed by industry benchmarking data from the Business Continuity Institute (BCI, 2022). Under the 14-day disruption scenario, the simulation projects a production shortfall of 40,000 units, equivalent to an estimated revenue impact of two million yuan at the company's average selling price. Inventory buffers are exhausted within five days of the disruption commencing, and the production line operates at zero capacity for the remaining nine days. Under the 30-day scenario, the production shortfall increases to approximately 85,000 units, with revenue impact estimated at 4.25 million yuan. A dual-sourcing scenario was also modelled, in which 40 per cent of the critical component supply is contracted to a secondary supplier. Under the same 14-day disruption applied to the primary supplier, the dual-sourcing configuration produces a production shortfall of 8,000 units, representing an 80 per cent reduction in the disruption impact. This finding provides quantitative justification for dual sourcing as the primary mitigation recommendation.

Critical Evaluation

The simulation evidence and theoretical analysis support a clear recommendation, but responsible analysis requires acknowledgement of limitations. Simulation models are simplifications of complex systems and are sensitive to the assumptions embedded in their parameters. Resource Dependence Theory, while providing a powerful framework for understanding supplier vulnerability, does not account fully for the relationship-specific investments and trust-based mechanisms that moderate the exercise of supplier power in practice (Cousins et al., 2008). A supplier with whom the buying organisation has a long-term collaborative relationship may behave differently under disruption conditions than the theory would predict based on power structure alone. The implementation costs of dual sourcing also require consideration. Tomlin (2006) models the conditions under which dual sourcing is cost-effective relative to single sourcing with buffer stock, finding that the optimal strategy depends critically on the probability of disruption, the cost differential between suppliers, and the demand variability of the end product.

Conclusion

This analysis demonstrates that Company X faces a significant and quantifiable supply chain vulnerability attributable to its structural dependence on a single tier-one supplier for a critical component. Resource Dependence Theory provides the conceptual framework through which this dependence is identified as a source of strategic risk, and simulation modelling translates that theoretical risk into specific, quantified projections of production loss and revenue impact under realistic disruption scenarios. The evidence strongly supports dual sourcing as the primary mitigation strategy, with the simulation demonstrating an 80 per cent reduction in disruption impact under a dual-source configuration. The limitations of the analysis identify the additional work required before implementation, but do not undermine the core finding that the current sole-source configuration represents an unacceptable level of operational risk.