The Quality score is the 0-100 number you see with every audit - a synthetic measure of your website's measurement health. It's worth understanding what this number expresses, and what it doesn't.
What goes into the score
The score is built from the results of all checkpoints covered by your audit:
Checkpoints are not equal - they carry weights reflecting their impact on data reliability. Missing transaction deduplication (which corrupts every revenue report) weighs more than, say, a missing coupon parameter. The heaviest problems are additionally flagged as critical - those are the ones that surface at the top of the Action plan. We don't publish the exact weights and thresholds: they're part of the audit methodology, and you don't need them to interpret the score.
How to interpret the number
Why the score can change "on its own"
Some checkpoints analyze the last 30 days of data (event continuity, channel conversions, the funnel). If something broke on the site between audits - a deployment overwrote the tag, the consent banner blocked measurement - the score will drop even though you "changed nothing" in GA4. That's not a quirk of the methodology; it's precisely the function recurring audits exist for: catching regressions before you notice them in your reports.
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