For about four months, I was convinced my email campaigns were underperforming. The numbers in Google Analytics showed almost no conversions coming from email. So I rewrote subject lines, changed the sending schedule, even hired someone to review the whole strategy.
Nothing improved. Or so I thought.
What was actually happening was that my UTM parameters had been set up incorrectly from the start. Every link in my emails was missing the source tag, so Analytics was lumping those visits into direct traffic. My emails were working fine. I just could not see it.
Where the mistake actually happened
A volunteer at my community centre had helped me set up the tracking links back in spring. She was well-meaning but had copied a template that used a placeholder where the source value should have been. I never checked it because the links clicked through correctly to the website.
Clicking through and being tracked are two different things. That took me an embarrassingly long time to learn.
What I do differently now
Before any campaign goes out, I send one test link to myself and check in real time whether it appears correctly in the Analytics live view. It takes about three minutes and has saved me from repeating this mistake twice already.
I also keep a simple spreadsheet listing every traffic source and whether it has been verified in the last 30 days. Nothing fancy, just a date column and a yes or no.
The lesson was not that analytics is complicated. It is that a broken setup gives you confident-looking data that points you in entirely the wrong direction. Checking the plumbing before reading the meter matters more than most people realise.