lean-ux

Use the standard format: "We believe [outcome] will happen if [persona] achieves [action] with [feature]." Every hypothesis must specify a persona, action, measurable outcome, and pre-committed success criteria before any design work begins.

Gather the cross-functional team for 45-60 minutes, generate assumptions on sticky notes, then plot each on a risk-versus-uncertainty matrix. Test high-risk, high-uncertainty assumptions first by converting them into hypotheses.

Lean UX focuses on design practice: hypothesis-driven design, collaborative sketching, and lightweight research within product teams. Lean Startup covers the broader Build-Measure-Learn business loop; this Skill points to lean-startup for that methodology.

Choose the lowest-fidelity experiment that answers the question: paper prototypes for flow validation, landing page smoke tests for demand, concierge or Wizard of Oz tests for solution value, and A/B tests only when you have 1,000+ users per variant.

Lean UX uses dual-track agile: a discovery track (hypotheses, experiments, research) runs one sprint ahead of the delivery track. Only validated designs enter the delivery backlog, and user stories carry a hypothesis and success metric alongside acceptance criteria.

Avoid paper prototypes when the hypothesis depends on visual design, animation, real data, or performance, and when stakeholders will not trust low-fidelity evidence. Climb the fidelity ladder only when lower fidelity cannot provide the needed confidence.