When I was a little kid I watched my dad cut the shell off a golf ball with the spey blade of his good ol' razor sharp Schrade stockman. The idea was to get the core of the golf ball, which is not unlike a rubber band ball, and light it on fire, and watch it dance and hop around when the rubber strands broke.
I thought that was the coolest thing ever when he did that. Later on that day, I found another golf ball and thought I'd try the same thing. I stole my dad's knife off his table, opened the scary sharp spey blade, held the ball between my thumb and index finger and started trying to cut the shell off.
The knife slipped right off the ball and right into the side of the first knuckle of my left index finger. Blood everywhere.
I guess my story isn't when knives go bad....it's when kids go bad.
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Didn't happen to me, but I was watching this redneck neighbor guy cutting on this dead snapping turtle (guess he was gonna eat it) with a cheap silver handled kitchen knife, and getting nowhere. I told him I had a good knife he could use, and went into the house and got him a small stag handled, German bird and trout knife that had an absolutely screaming edge on it. (Sharpest knife I own, and have ever seen in my life.) I guess he was used to sawing away with the dull knife, and when he got my sharp knife he was a bit too careless with it. He had the turtle shell in one hand, and stuck the knife in the turtle, and pulled up hard with it edge up. The knife glided right through that turtle shell and right into his hand. There was about a 4 inch gaping wound in his hand, and it was bleeding profusely. I can still remember him putting a water hose to it, the blood flowing right along with the water.
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Made a mistake of letting a dumb jock guy in high school drama class look at my Spyderco Endura. I was building sets for an upcoming play, and it came in handy cutting canvas, wood etc. The guy asked me if he could see it, and I handed it over. He asked "Is it sharp?" and before I could answer him, he dragged the razor sharp edge across this random girl's arm sitting next to him, cutting her wide open. I grabbed the knife from him, and jumped his ass so hard. I wanted to kill this guy.
anyway, those are my knife stories.