It happens, more than it should and it’s annoying…..web developers inadvertently break tracking while developing websites.
The problem is – the earliest sign you have that things have gone south is 24 hours later the revenue or conversions look unnaturally out of trend. By this point, you’ve lost a bunch of data, Year on Year trend is screwed and you’re adding annotations to Google Analytics to explain what happened in the hope that someone looks at the annotation next year when doing their Year on Year comparisons.
If you’re working on a site that has ongoing development, this type of problem can seem to happen almost once a month.
So what can be done?