When a visitor arrives at a home and presses the doorbell button, the action sends a signal inside.
Immediately after the press, the exterior remains unchanged. The front door stays closed, the windows show no activity, and the porch appears still and quiet. No sign of response is visible from outside.
Time passes without alteration to the scene. A minute or longer may elapse as the visitor stands waiting. The house continues to look undisturbed, with the same closed door and inactive windows.
Eventually, the door opens. The resident steps into view, making the outcome of the button press observable.
The sequence from press to door opening reveals latency: the initiating action precedes the visible result by a distinct interval.