If you read Scan Barcode or QR Code | Glide Docs , you will find this mention on the FAQ section:
Is there a quota on barcode scanning? While there is no quota on barcode scanning, if the scan results in a new row addition or a row edit, it will count as an update.
I have never succed in creating a QR code scanning without 5 updates, so maybe it would be recommended to rewrite the answer to this question, because the right answer is not “an update”, but 6 updates (5 from scan action and 1 from raw addition or edit).
So do you suggest unifying these two questions & answers?
Yes, and re-wording the first answer, because “there is no quota on barcode scanning” is misleading. I have an event and I expect more than 20k scans, and based on this instruction I have made a strategy for an app, expecting 20k updates, so I have prepared the budget for this amount. When I started to implement the solution, the scanning action always return the message “Each run uses 5 updates” - so, there is a “quota”, actually. My initial 20k updates estimate is, in fact, 120k updates - and the budget is on fire! 
Quota does not equal updates. They are two completely different things. The statement “there is no quota on barcode scanning” is 100% accurate.
And the second FAQ very clearly states that each scan consumes 5 updates.
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