If cables can break-in, can they then wear-out?

I have used cables that were 15 years old...if there's a difference... my degraded hearing....I couldn't tell.

Good question....but a non issue.

Cables...atleast my experience...do break-in or equalise..the biggest proof to me is the change in sound dispersion from my speakers...directional to non directional in varying degrees....and it is not subtle or imagination.

To prevent cable break out after break in - purchase some cable anti wear out oil - it is the lack of lubrication that kills the di in dielectric - or did it put the ape in apricot? Either way - you must be sure that the cable anti wear out oil was made from the same snake oil that caused the cable to be so special in the first place - it's just later in the season. (this editorial comment was not meant to insult snakes or reptiles)

In professional recording studios ALL cables are replaced whenever there is a perceived change in audio quality or any electrical problem with the equipment. Although the cost of replacing all of the cables is high it is cost effective in reducing downtime. Replacing the cables will resolve 90-95% of equipment related problems immediately.
So cables do "wear out" in the sense that they can malfunction at any time, whatever the actual cause.

Musicnoise puts the "fun" back in this dysfunctional thread.

Yes, when cables wear out, you'll lose air around the instruments, palpability, PRaT, gestalt, harmonic richness, rhythmic chunkiness, etc. Even your wife will be able to hear it from the next room, it's not subtle. 8^)