Perception of the world is so intimately bound with time that things that happen outside of normal time perception go unseen, unnoticed.
For thing that happen slowly like trees growing in the garden or large constructions sites this is obvious. What happens though when perception of time is slowed down?
As time slows people going about their business become fuzzy and blurred. Slow it down further and they become like wispy ghosts. Eventually they are gone completely.
Photo: Robert Rath, 'Nobody Saw Him Leave' 0.3s f/14 ISO100 15mm