What are design principles in UX?
Design principles are a set of guiding values that articulate how a product should be designed and why. They reflect the priorities and commitments that should shape every design decision. Well-crafted design principles help teams make consistent decisions independently, resolve disagreements by reference to shared values, and communicate the product's design philosophy to new team members and stakeholders.
What makes design principles effective?
Effective design principles are specific enough to guide real decisions, not generic enough to apply to any product. "Make it simple" is not a useful principle because it does not help teams decide what tradeoffs to make. "Simplify the decision, not the power" is more useful because it specifies the direction. Effective principles often come in tension with each other, reflecting real tradeoffs that design must navigate, and having both principles explicitly stated helps teams discuss those tradeoffs deliberately.
How do design principles relate to design systems?
Design principles provide the philosophical foundation that design systems encode into concrete components and patterns. A principle like "Make the system's behavior predictable" translates into consistent component behavior, naming conventions, and interaction patterns. A principle like "Reduce cognitive load at every step" translates into progressive disclosure patterns and limited choices per screen. The design system is the operational expression of the design principles.