Working Backwards: Insights, Stories, and Secrets from Inside Amazon

by Colin Bryar

Before you can improve any system . . . you must understand how the inputs affect the outputs of the system. You must be able to change the inputs (and possibly the system) in order to achieve the desired results. This will require a sustained effort, constancy of purpose, and an environment where continual improvement is the operating philosophy.2 Amazon takes this philosophy to heart, focusing most of its effort on leading indicators (we call these “controllable input metrics”) rather than lagging indicators (“output metrics”). Input metrics track things like selection, price, or convenience—factors that Amazon can control through actions such as adding items to the catalog, lowering cost so prices can be lowered, or positioning inventory to facilitate faster delivery to customers. Output metrics—things like orders, revenue, and profit—are important, but they generally can’t be directly manipulated in a sustainable manner over the long term. Input metrics measure things that, done right, bring about the desired results in your output metrics.