Shaving off the underside of your hair is an age-old trick for keeping cool in the summertime. It's also a way to thin out thicker locks. Kylie, however, probably reached for the razor not out of practicality but as a way to switch up her ever-evolving look.
Although it seems like the last thing she'd do now, Kim apparently had a similar half-shaved style in her youth. "I did that haircut when I was 12 years old. The cool thing is to do the back of your head and then wear a ponytail," the former tween rebel told E! "I might do it. I should." Couldn't let your sister have this one, could you, Kim?