Signups doubled, but first purchases did not. What do you inspect first?

Check whether the new signups are comparable: audience, source, observation window and eligibility. A change in traffic mix can affect purchase behavior even when the registration flow works correctly. Separate mature cohorts from people who signed up yesterday.

Then inspect the path to the first useful task and purchase. Look for a specific friction point rather than assuming all new users need more onboarding messages. The useful question is where qualified intent fails to progress, not whether the signup chart looks healthy.