The modified date and time in the General Metadata section of the inspector does not update when you make changes to the document it inspects. Even when the allotted time passes and Scrivener automatically saves the document so the asterisk in the title bar goes away, the modified date and time don’t change.
That can be a problem if also working in the other editor, notes, and elsewhere, and you use that date and time to check whether you’ve applied changes you are considering.
The workaround is to select a different document and then return to the first document. It will then show the correct modified date and time.