could anybody answer this question about the short story 'there will come soft rains'

Why are thereso many references to the time of the day?what does the final sentence suggest?
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Irony. The house is obsessed with time because of what all its human occupants should be doing at each time, when in reality they are beyond matters of time. Fits with the theme of the poem from which the story derives its title--spring will arrive, but who will be there to "know" it's spring?