To be fair to all here, she also pointed out that it is a cheapy and not a genuine Apple item.
But I sort of assumed Apple was protective of its brand and would make accessory manufacturers jump through some quality hoops before selling them the Lightning bit.
The break was in the non-Apple end - the USB connector rather than the Lightning connector.
Not only were some of the wires stripped back too far and in danger of shorting, but the strain-relief gunge (below) was not properly placed - it fell off when picked at - and had not protected one of the wires.
I trimmed and re-soldered the right hand two connections and filled it up with RTV silicone in the hope that it won't break again for a while - and am slightly ashamed that I didn't re-solder everything else before I shoved it back together but time, as always, was limited.
Stay away from cheap cables?
And, pity the poor sods that have to rush making them.