I've had two minor injuries from angle grinders.
One, the wheel grabbed a piece of sheet metal which I was trying to avoid. Result: a small divot near my wrist. Could have been tourniquet and Emergency Room.

Another time i recal, i was working down low, and the wheel grabbed my coveralls. I got a deep scratch across the knee. Could have been a permanent limp.

Both times were result of a momentary lapse of attention.

My angle grinder is my favorite tool, and probably the most dangerous. I have removed the guard on occasion, but it always goes back on as soon as possible.