Two channels can deliver the same cost per signup and wildly different businesses. One brings customers who stay for years; the other brings trial tourists who churn before the first invoice. Without cohorts, both look identical in a weekly report.

Group by acquisition source

Build monthly cohorts by first-touch channel and track paid retention at 30, 90 and 180 days. The gaps appear quickly, and they are usually larger than anyone expects.

Measure payback, not just CAC

Divide each channel's CAC by the gross margin its cohorts generate per month. A channel with a higher CAC but a six-month payback often beats a cheap one that never pays back.

Feed it back into budgets

In Skyroot, cohort views sit next to attribution, so the weekly budget review can weigh retention alongside ROAS. Teams that make this switch typically move 15–25% of spend within a quarter.