Last year I posted about a firm I'd found who offer one and a half grand mains leads! But the audiophiles have outdone themselves in the emperor's new clothes stakes;
Cables should be burned-in or conditioned on a regular basis for optimum performance. In normal use, there is a leakage current from electrical equipment which causes the cable to take on a charge; cable conditoning will neutralize this charge.These people should be prosecuted - they are liars.
New cables often have very high levels of electrical charge caused by the production process. In addition, gases are often trapped between the insulation and the conductor during manufacture. This can often result in new cables sounding brittle, bright, and lacking in detail. These charges must be neutralized if a cable is to ever achieve its maximum performance.