Picture a SaaS startup with a dashboard that looks great. Sign-ups are up every single month. The marketing team is celebrating. The founder is pitching investors.

And yet revenue is barely moving.

This is one of the most common traps in early-stage SaaS, and it has a simple cause: the team is measuring customers acquired , not customers kept .

In this article I'll walk through a realistic (hypothetical) startup, calculate the numbers step by step, and show how basic analytics exposes a problem that more marketing spend can never fix.

Note: All numbers below are illustrative, built to demonstrate the mechanics.…