The only people who ever review items like cables are ones who ran into failures, so that’s a very skewed sampling.
[1] http://www.amazon.com/AmazonBasics-USB-Male-Mini-Cable/dp/B0...
[2] http://www.monoprice.com/Product?c_id=103&cp_id=10303&cs_id=...
Either there's a big difference in quality between the cables Apple sells on Amazon vs the Apple Store, or there's something else going on.