This is a myth. Ideally, an earphone is supposed to be weightless. It is the main USP of the product. Further, sturdiness is one reason to remain strong and durable for long. But an earphone’s durability depends on many other factors. The quality of the wires, the wire coats is one side. The quality of the drivers, as well as the polymer in which it is made, is on the other. For sure, the weight of an earphone does not guarantee durability and there are heavyweight earphones too.