Simple. The listeners prefers the sound with a particular cable. That's what most mean when they say it is "better".
Different wires might have different electrical properties that account for how they perform in a particular system. But these are not well defined or known, and there are certainly no commonly accepted standards that can be applied, so picking cables based on technical specs is laregely a crapshot, at least compared to amps, source gear, speakers. Also the differences among cables regarding sound in a particular rig may be significant, but generally less so than with the main components in teh system, which makes quantifying differences even harder in practice.
The value of certain aspects of cable design might be more apparent than others. THings like whether shielded or not (to protect against potential external sources of noise like EMI or RFI) and material used to construct the wire, for example, silver versus copper, each of which has well known electrical properties and differences that might directly translate to a different sonic signature in general. Gauge of the wire used is another that might be determined to deliver different relative sonic signatures in a somewhat predictable manner, but again truly quantifying these things is virtually impossible in practice. USe of network devices to affect the eletronic properties of the wire in a pre-designed manner is another design aspect that might deliver somewhat predictable results.
In the end, best to try/listen to a variety of inherent designs and decide what sounds or works best in each case.
Different wires might have different electrical properties that account for how they perform in a particular system. But these are not well defined or known, and there are certainly no commonly accepted standards that can be applied, so picking cables based on technical specs is laregely a crapshot, at least compared to amps, source gear, speakers. Also the differences among cables regarding sound in a particular rig may be significant, but generally less so than with the main components in teh system, which makes quantifying differences even harder in practice.
The value of certain aspects of cable design might be more apparent than others. THings like whether shielded or not (to protect against potential external sources of noise like EMI or RFI) and material used to construct the wire, for example, silver versus copper, each of which has well known electrical properties and differences that might directly translate to a different sonic signature in general. Gauge of the wire used is another that might be determined to deliver different relative sonic signatures in a somewhat predictable manner, but again truly quantifying these things is virtually impossible in practice. USe of network devices to affect the eletronic properties of the wire in a pre-designed manner is another design aspect that might deliver somewhat predictable results.
In the end, best to try/listen to a variety of inherent designs and decide what sounds or works best in each case.