Make your design insensitive to uncontrollable influences.
Robust design helps you reduce the sensitivity of your innovation to uncontrollable noise variables. For instance, an automotive designer might use robust design to develop a more fuel-efficient car engine that is less susceptible to the vagaries of customer driving habits and environmental conditions. Or a physician's office might design a patient-scheduling routine that is minimally impacted by variations in staffing or patients arriving late.
Throughout the life cycle of a product or service, variation can and will occur. Because variation negatively impacts performance, the resulting customer experience will also be negative when the product or service fails to live up to expectations. Robust design seeks to predict variation before it occurs, and then prevent or minimize it through design.
To undertake robust design, you'll definitely need help from an experienced engineer or statistician familiar with this approach to testing and analysis. You'll also need to know how to apply several other techniques in this book, including Functional Requirements (Technique 33), Axiomatic Design (Technique 34), Design Failure Mode and Effects Analysis (Technique 44), and Design of Experiments (Technique 53).