The USB-C charge cable included with Macbooks before June 2015 "might fail due to a design issue," according to Apple.
Apple
Apple will replace those cables for free, if you bring it into an Apple Store or contact Apple Support.
Apple's Macbook is the first laptop in years to ditch the magnetic MagSafe connector for USB-C, a new reversible standard connector that is increasingly being used on phones and tablets.
Google uses the USB-C connector on its latest Nexus smartphones as well as on its Chromebook Pixel laptop.
From the replacement page:
Apple will provide a new, redesigned USB-C charge cable, free of charge, to all eligible customers. This program also covers Apple USB-C charge cables that were sold as a standalone accessory.
For MacBook owners who provided a valid mailing address during the product registration process or Apple Online Store purchase, Apple will send you a new cable by the end of February 2016.
Developing...