damaged motor

My Phantom 3 Standard has never been crashed, dropped, or hit against anything (to my knowledge), and it's only been flown maybe 8 times. However, the threads on the motors are all slightly damaged somehow, with damage ranging from "barely noticeable" to "I had to take a knife and bend the...

I was installing props and found out one of my motors didn't feel right. It felt stiffer and didn't move 'robotically'. When the motors started, it squeaked on and off at idle and disappeared when revved up. As a cautious person, I bailed and called it quits for the day. I took her home and had...