The spots of paint are all that is left of the people who lived in the house.
There are no people alive to tell the story in “There Will Come Soft Rains.” There has been some kind of recent catastrophic event that seems to have caused an apocalypse. It appears to have been some kind of atomic bomb, because it disintegrated the people. Since the family was outside when it happened, they became nothing more than paint spots on the wall.
We are told that the “west face” of the house is almost completely black, except for the spaces where the people were standing in front of it.
Here the silhouette in paint of a man mowing a lawn. Here, as in a photograph, a woman bent to pick flowers. Still farther … a small boy, hands flung into the air; higher up, the image of a thrown ball, and opposite him a girl, hands raised to catch a ball which never came down.
The family was on the lawn, with the man moving and the woman picking flowers while the girl and boy played catch together. The bomb went off and blackened the side of the house, leaving gaps where the people had been standing. All of the people are dead, but somehow the dog survived—barely.
A dog whined, shivering, on the front porch. The front door recognized the dog voice and opened. The dog, once huge and fleshy, but now gone to bone and covered with sores, moved in and through the house, tracking mud.
The dog is the only living being still alive, but it is not really alive. It has been poisoned by the bombing, and is clinging to life. Since the house is automated it is still able to get in, but it dies there. The dog lets us know that the apocalypse was recent.
This story is clearly a cautionary tale. The house is practically alive with technology, but technology killed all of the people. In trying to make life easier for themselves, the human beings destroyed themselves. Sometimes technology can be a Pandora’s Box, unleashing destruction that was never expected.