Interconnects, some have directional indicators, why?

I'm curious as to why some interconnects are directional? Is there a physical internal difference and do they generally sound better and cost more than non-directional cables? Thanks for your interest.
phd

My view on it and the way I always make them up on RCA's leads with 2 x internal conductors and a shield, the shield is only used as an RF trap and only connected at one end, (not used as the signal return).
In this case the end that the shield IS connected to the ground wire should be at the least sensitive, being the poweramp not the source, as to dump the RF it catches to ground of least sensitive part of the chain, being the poweramp, not the preamp or the source.

Cheers George   

Arrows on all other kinds of cables -- XLR, speaker, power, and data -- are utterly meaningless from an electrical standpoint, since audio signals (and wall voltage) are alternating current and interact with conductors the same way in either direction.

I'm only sure it is useless for XLR cables, since you can plug them only in one direction.

@jea48 so-- if the electrons flow easier one way then the other (a reasonable interpretation of the first paragraph), what happens? Do they not all make it back on the return cycle?

Obviously the answer is ’No.’, as an excess of electrons would occur at the receiving end, which would mean that there would be a negative DC voltage generated. Since that doesn’t happen, we can assume with a great degree of accuracy that the electrons are in fact flowing either way with equal ease.

Interconnect cables are not diodes. The reason they might be directional has to do with how the shield is arranged. Usually you want the shield grounded at the source only. While its not as good as balanced operation for low noise, its better than just a regular shield with single conductor inside.

So I think we can consider the quote from herman to be debunked.

Crystal orientation in OFC and in Ohno Continuous Casting manufacturing predicts that there is directionality in metals that may influence the sound quality.

Usually you want the shield grounded at the source only.

I believe the RF should be dumped into the ground of the least sensitive to RF end, being the poweramp.
But hey! 6 of one 1/2 dozen of the other.

Cheers George