The law of pedestrians (theory)

The law of pedestrians is a theoretical law that notes that, whenever a car has to leave a car park, especially via reversing or some complicated manouver, a pedestrian has to mandatorily appear, get in the way and impede progress.

Possible reasons
Reasons why the law of pedestrians occurs might include that car parks are often located in human-intense locations (EG centres or markets), or that cars are parked in areas which have a high thorough-fare of pedestrians or similar (such as a housing estate), or simply a result of urban expansion and density.

However these factors fail to explain timing (this might be due to inefficient, inconsistent or random walking-return routes of pedestrians to their cars) of how the pedestrians appear just at the right time to impede car park leaving operations (EG reversing) or why pedestrians seem to be oblivious or so aggressive (IE standing next to a reversing car which may not spot them resulting in an accident), especially given size differences.

It could be due to a largely impatient nature that pedestrians use a reversing car as a moment of opportunity in order to get a slightly shorter return path (at the loss of inconveniencing the driver), however it fails to explain why they would gather in that particular area at that particular time.

Related:
See also:

The law of cars (theory).

Zombie (human AI).