What is the origin of the idiom "one-track mind" and when to use it?

The idiom "one-track mind" originated from the concept of a train running on a single track, symbolizing a singular focus or preoccupation. It refers to a person who is excessively fixated or obsessed with a particular topic, idea, or desire, often to the exclusion of other thoughts or interests. The phrase is used to emphasize the narrowness of the individual's thinking and their inability to easily shift their attention or consider alternative perspectives.