With the iPhone 5, Apple introduced the new Lightning connector, effectively retiring the old 30-pin dock connector to the dust pile of the past. However, Lighting cables have been in limited supply and currently have a two to three-week wait time in Apple's online store.
The reason for this, according to KGI analyst Ming-Chi Kuo, is two-fold: change in supplier weighting and resulting low yield rates.
As noted by AppleInsider, Kou maintains that because the Lightning connector is much more complex to build and requires new methods of production, the initial yield rate will be lower. This should change as production goes on, but for now Apple's suppliers physically can't make as many Lightning connectors as they could dock connectors.
Another factor resulting in Lightning connector shortage is the fact that Apple changed the supplier weighting for Lightning connector production. For dock connectors, Foxconn made up to 60 percent of all units, but since Foxconn has been having some trouble with production, Apple now gets 60 percent of Lightning connectors from rival Foxlink. Because Foxlink has a better yield rate than Foxconn (who now makes 40 percent of the Lightning cables), but not as high a yield rate as it did for dock connectors, the output is still much lower, which means more time to get the new cables in the hands of iPhone 5 users.
As time goes on, production rates and yields are sure to increase. Until then, you may have to wait a few weeks before you can pick up extras of Apple's latest cable wonder.