If you look along a straight road, "the parallel sides of the road appear to meet at a point in the distance. This point is called the vanishing point.

Suppose you want to draw a railroad track that vanishes into the distance, the rays from the points at a given distance from the eye along the lines of the tracks are projected to the eye. The angle formed by these rays decrease with increasing distance from the eye."

The visitors who aren't standing in the proper angle won't have a clue about the concept. They will fail to understand the meaning of the apparently irrational lines & curves on the walls. These illusions take shape when the viewer finds that 'sweet spot'. Yes this is an incredibly unique perspective art.