What did you find the first time you actually instrumented your funnel?

I finally set up proper conversion tracking this week. I had put it off for a fortnight because it felt like plumbing rather than progress. It took about an hour.

The first thing it told me was that one of my funnel events has never fired. Not rarely. Never, not once in 28 days.

People run a scan. People hit the gate. People hand over their email address to unlock the report. And then nobody clicks through to the app. The step I had assumed was the easy one, the one after they have already given me something, is where it stops dead.

What makes it worth posting rather than just quietly fixing: I had spent the previous two weeks working on the top of the funnel. More traffic, better ad copy, keyword research. All of it aimed at a stage that was already working, because I had no way to see which stage was not.

The part I keep turning over is that the absence of the event was the finding. Not a low number, a zero. A low number I would have argued with. A zero I could not.

So, two questions. What did you find the first time you actually instrumented something? And had you been working on the right part of the product before you looked?