I have noticed that the siding of single family homes in Colorado, at least my made-in-the-70's neighborhood, does not extend down to or into the ground. Why is this? Why not have siding (vinyl, brick, stucco, etc) go into the ground?
I seem to recall other buildings, such as apartments or schools, have siding that goes into the ground. Maybe this is just poor observation skills at work or due to sidewalks. This small gap between siding and concrete makes a wonderful little place for animals to get into the walls!
EDIT: How High Should The Siding Be Above Ground Level? does not answer this question. It's asking how high and I am asking why. The difference here is asking for a number and why you would even bother.