Apple first introduced the 12-inch MacBook in 2015, and the device was marketed as a thin and light notebook for the consumer market. However, the machine was highly compromised due to its pokey entry-level Intel processors (which often throttled due to the fanless design), just one USB-C port, and the poorly received butterfly keyboard.
After

Source: Hot Hardware – Apple Hints At Possible 12-Inch MacBook Return In Customer Survey