How can I make iPod 30-Pin cables last longer?
The answer to the question comes down to how the cables are treated over their life time.  This applies to pretty much all cables regardless of the manufacturer or type (USB, network, charging/power, etc.).  It's also important to note that Apple used a higher quality, more flexible cable (it feels softer and thusly, more premium in the hand).  The downside, it's not as durable the cheaper, more &quot;plastic-y&quot; cables.
Coil your cables
The cable will have a natural &quot;loop&quot; to it and if you coil it following that loop you will preserve it for years to come.

Follow the natural loop and coil your cables so that there's no strain on the adapter ends

Do not bunch them up in a tightly wound loop and don't &quot;fold&quot; them over.

Most importantly, never knot your cable into itself - it's not rope.



The photos above are of my actual genuine Apple 30 pin cable that must be pushing at least 10 years of age.  The top photo is the exact way that I store my cables even when traveling.
For reference, this is the exact same way I coil my cable on my Microsoft Surface Pro tablet that I keep in my briefcase.

Use strain relief where possible

Tie-wrap your cables in a bunch to prevent excessive strain being applied to the connector ends

Use cable management gadgets to prevent the cables from going over sharp edges

Use &quot;service loops&quot; judicially when routing cables behind a desk or furniture.  Loosely coiling the wire and loosely wrapping them with Velcro or plastic will allow for movement without binding on the connectors.



I've followed these practices for the better part of 20+ years (obviously not with just Apple cables) and can honestly say that I have a significantly greater likelihood of replacing a cable because I lost it versus it becoming damaged.