The idea
“Growth is slowing” is a concern, not yet a problem you can solve. Structure gives it boundaries: Which customers, products, regions, and periods account for the change? Is acquisition weakening, retention falling, or spending shrinking?
Break the question into distinct branches, form a few plausible hypotheses, and identify the evidence with the greatest power to eliminate one. Do not collect every available number. Sequence learning so each answer changes what you investigate next.
Make it concrete
A subscription business sees slower revenue growth. The team separates new revenue from existing-customer revenue, then separates retention from expansion. One cut shows stable acquisition but falling renewals in a single segment. A vague growth initiative becomes a focused investigation of that segment's renewal experience.
Try it
Rewrite one broad problem as a precise question. Split it into three non-overlapping causes and name the first piece of evidence you would seek.