EDIT: Even if the cable is wired and built correctly (which is apparently difficult for manufacturers to get right), cables fray and tear all the time. I foresee a lot of dead electronics upcoming.
As for cables fraying, the most common result is an open (an unconnected wire). If two of the wires get damaged at the same time, you might get a short (and the USB standard mandates that a short causes no damage to devices). But reversing a pair of wires? It's ridiculously unlikely that fray and tear on a cable not only severs a pair of wires, but also reconnects them backwards!
That's akin to saying:
The US power grid is a bad standard because I wired up my house wrong and it burned down.
The US power grid is a bad standard because I wired up my house wrong and it burned the power station down.