Because it's drawn to give off an angle they draw it flat like that in order to generate the illusion of 3d on a 2d plane but then either someone edited it or this is a gag in the show where its actually just a steep drop down. A play on that illusion vs the reality.
What if we make a luxury multi-storey condo in a side of an extremely steep shore hill with a view on to the water. The hill side will essentially be glass to allow a lot of light into the rooms and the rooms go along the hill. The elevator will go down from the top into the ground and the parking garage will be on the surface which may or may not be enclosed. Imagine sitting at your kitchen table watching the sunset through a glass wall/very large window
Good idea in terms of design, bad idea in terms of engineering and corrosion.
The cliffsides slowly but steadily are washed away by water, and occasionally, once enough structural damage has been wrought, big chunks of it falls into the sea as a rock slide.
as a kid i was always afraid of the steep roads in my town
i was scared i was going to lean back one day and fall backwards
because the roads were on insane angles i would nearly slide down them
it sucked