The threshold is the frame that permits performace to happen. It manifests here through the material pattern and texture of the flooring.
This image taken in Heathrow’s Terminal 5 luxury brand retail spaces.
What “thresholds” stage performances at a building scale?
In the image, that threshold gives authority to the customer to buy, it gives expectations to the customer to be served, it gives the employees the “cue” to greet you. Outside of that threshold, you are one of the many.