820-4924 trackpad cable insights?

[Revive]

This particular model seems to suffer from a very high trackpad-cable failure rate which causes the trackpad and keyboard to lose connection.
Just curious if anyone has any insight as to why this happens? Seems so odd that they would fail suddenly since their just sort of inert in the case and it can happen out of nowhere?
Its like the zombie of the 2012 13" MacBook Pro hard-drive cable has come back to haunt the retinas.
I'm guessing it has to do with the it shorting at a bend point (why do they put so much slack on it anyway!?).
Any idea why this seems to happen so much?

 

[dukefawks]

The same old. Copper traces are bend and the bottom cover is touching the cable and flexing it. Flex it often enough and it will crack. Also copper can suffer from stress corrosion in the bended region, which will not help the case.