How would you measure the ROI of a product redesign?
Model answer
Model answerProduct redesigns are notoriously hard to attribute because they affect everything at once. I'd establish a pre-redesign baseline for 3–4 key metrics — task completion rate, time-on-task, NPS, and conversion — and hold these as the control. Then run a phased rollout: 10% of users get the new design, 90% keep the old one. After 4 weeks, compare. The trap to avoid: measuring only what improved and ignoring what got worse.
Framework · Dual Metrics Model
- UUser metrics
Task completion rate, time-on-task, error rate, satisfaction score - BBusiness metrics
Conversion rate, session duration, support ticket volume, NPS - GGuardrails
Identify metrics that must not decline — a beautiful redesign that hurts conversion failed - TTime to measure
Redesign effects often take 4–8 weeks to stabilize — don't read results too early
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