I've designed bass strings for a few different brands. I've also consulted with many brands as they're developing them. In fact, I got two sets from a well-known brand two weeks ago I'm messing with.
Anyhooo......Several years ago, a well-known brand was sending me set after set for testing and feedback. When I was putting one set on and tuning it to pitch, a string broke. It broke at the exposed core that goes around the ball end. The string actually DID whip towards the headstock and the broken, exposed core put about a 1/2" "slice" on my cheek. I sent the company a picture of that.