Analysis of Structure and Plot Advancement

Read the following excerpt from a fictional narrative:

Old Mr. Jenkins was known around town for his peculiar habit of collecting clocks. Each tick and tock echoed in his cluttered home, like a symphony frozen in time. One summer evening, a mysterious stranger appeared on his doorstep, bearing an old clock that had not ticked in years. The clock, once belonging to Mr. Jenkins' late wife, sparked memories and emotions long buried. Over the next few days, Mr. Jenkins began to reminisce about the moments tied to each clock in his collection, revealing fragments of his past.

Consider the role of structure in this excerpt. How does the introduction of the stranger and the clock serve to advance the plot?