What is the origin of the idiom "money for old rope" and when to use it?

The origin of the idiom "money for old rope" is believed to have come from the practice of recycling or reusing old materials in various trades. In the past, ropes made from natural fibers were widely used, and when they became worn or damaged, they were often sold as scrap. Today, it is used to describe a situation where someone is making money or earning a profit with little effort or by doing something that requires minimal skill or investment.