Mine fray constantly. I've never owned an apple device that HASN'T had terrible cords. I googled about why their cords are so crappy and found a thread on reddit with tons of people complaining. Apparently it's because the designers at apple thing cord reinforcement is not aesthetically pleasing. Sucks, I love their products, just wish their cords lasted longer.

https://www.thrillist.com/tech/nation/why-apple-hasnt-fixed-...