Visible stop cues must be provided
Aliases: catch-up marker · end-of-feed state · "you're all caught up"
What it is
A stopping cue is the interface's own signal that a round has ended: an "you're all caught up" terminal card, a time separator, a genuinely-exhausted marker. In feeds that removed natural boundaries, it is the structural pause put back by hand — a place where those who want to stop can actually stop.
Why it happens
Self-interruption needs an external occasion: judging "enough" requires a node at which the judgment can occur. A stopping cue creates that node, slicing an unstructured stream into psychological rounds; when it appears, the default of continuing is briefly suspended and the user gets a nearly free moment of reevaluation. The cue's power depends on credibility: if new content still loads after "you're done," the cue is quickly learned to be noise and loses force. This tracks the general law of cue decay — repeated, unchanging signals lose their arousal value through central habituation, and the remedy is restraint in using cues, not louder ones; the mechanism is covered elsewhere in full, and only its conclusion is used here.
Where it stops holding
Stop cues serve use that wants to stop but lacks an occasion; they do nothing for retrieval tasks — searchers need a true marker of result exhaustion, not a staged pause. Too many cues degrade into a new noise source: multiple rest cards in one stream turn pausing into decoration. Commercial content pools usually exceed any reasonable session, so "all caught up" only holds for genuinely finite feeds (friends' updates, subscriptions); for algorithmically unbounded streams the anchor must be time or count, never a fabricated exhaustion.
Applying it
Treat the two stream types separately. Finite pools get a true terminal state: an explicit "you've seen all updates" with a source count, and nothing loads afterward. Unbounded streams get time or count segmentation: at fixed intervals, a pause card that requires a click to continue ("you've browsed 20 minutes") — a real gate, not a decorative banner. Both cue types are dismissible, and dismissal must not bring the cue back in another costume. Verification: log continue-versus-exit rates when cues appear, and track for weeks — if the continue rate climbs back over time, the cue has habituated; lower its frequency or move it, do not amplify it visually.