: an unplanned route or path (such as one worn into a grassy surface by repeated foot traffic) that is used by pedestrians in preference to or in the absence of a designated alternative (such as a paved pathway)
There's a concept in landscape architecture called a desire line. It refers to a path worn into the ground by foot traffic, in defiance of the planned curves of sidewalks and roadways. Henry Grabar
This is the authoritarian approach to erasing a desire line: block it off with some type of obstacle—a fence, a bush, a pile of brush, a sharply (if, in this case, politely) worded sign. Robert Moor
The proposed fence would not enclose the parking lot, only limit its use as a desire path. Zachary Oren Smith