What the Gamma watermark checker report actually tells you
Five rows: file type, file size, units scanned, whether a Gamma watermark was detected and how many objects, and whether any of it is flattened. If objects were found, a download button for the cleaned file appears with them.
Units scanned is the number that catches mistakes
For a PDF this is the page count, because the Gamma watermark is repeated once per page rather than stamped at document level. For a PPTX it is the number of slide masters and layouts examined, which is why it never matches your slide count — the badge lives on the templates the slides inherit from. If the PDF number is lower than your page count, you opened a different file than you meant to.
A detected Gamma watermark means objects, not pixels
The row reads "Yes" followed by a count, and that count is how many discrete objects carry the gamma.app or gamma.to link. A PDF at 40 pages typically reports 40. Zero here does not mean your file is clean to the eye; it means nothing in the file structure is linked to Gamma, which is a different claim and the next row explains why that matters.
Flattened risk is the row that decides everything
When this reads "Yes", part of the Gamma watermark has been merged into a page image and no object exists to delete. That is a structural dead end, not a bug, and it is the single most useful thing the checker tells you — because it tells you before you download, not after you have shared a file that still shows the badge.