Abstract
In the early onset of the COVID-19 pandemic in the U.S., consumers experienced surprising shortages of essential goods that appeared to be unrelated to the pandemic: toilet paper, yeast and flour, and meat cuts. The usual explanations-attributing these shortages to demand spikes-often failed to provide an adequate explanation or predicted only temporary shortages. But these shortages ended up being real supply-chain struggles for which the true causes revealed a deeper set of unusual causes. Our detailed analysis of these supply chains identifies overlooked failure factors and hidden causes. We conclude with the profound lessons learned from the pandemic crisis on supply chains and the implied challenges of building resilient supply chains for the future, which require rethinking the relevant systems we plan and optimize. The level of investment required for building firm-specific redundancy of assets and operational flexibility might be prohibitive for any one firm, or their financial stakeholders, to pursue and accept.