I had a trio of D12-0's CATO back in the 90's, long before I was on the internet, and found out about MESS reports.
I had a couple of packs of motors that I had purchased at the same time. However, I didn't know about batch numbers, so they all looked the same to me. Three of them worked fine... However...
The first of the bad batch exploded on the pad. It managed to ignite the sustainer (Estes Magnum Payloader), but the force of the detonation knocked the sustainer's motor mount loose, and it pushed its way up inside the body tube at an angle. The resulting flight is reminiscent of a ship launched Tomahawk missile, where the rocket is flying nose up, but at an angle. However, it didn't gain much altitude and crashed into the field before the ejection charge fired.
The 2nd was a Warp II that blew on the pad. We were launching on a school's baseball diamond due to the winds and the shape of the field. The force of the shock wave visibly flexed the glass windows of the house just on the other side of the fence. Turned out that there was a wedding party going on, and a number of highly annoyed guests came out to yell at the "kids" blowing up fireworks so close to their house. When they saw me on my butt, and the shredded remains of the rocket laying around they got curious and watched me clean up the mess, and launch the remaining rockets.
Realizing that I had a bad batch of motors, but not knowing how to identify which was bad from good, I used a scratch built rocket to launch the remaining motor. Sure enough it blew, and the shredded remains of the rocket fluttered down like confetti around us. We were laughing our A$$3$ off, when we started looking for the remains. Just as I asked "Where's the nosecone?", I hear this whistle and dull thump close behind me. I turn, and told my friend... "Well, here's the parachute." (still wadded up, about 6' behind us) and went to pick it up. Problem is, it was pinned to the soft damp ground of the soccer field by the nosecone (full of clay). I managed to get the nosecone out of the ground scratched up, but otherwise intact. Apparently when this one detonated, it fired the nosecone like a bullet, straight up. We got lucky that nobody got hurt, or anything got damaged.
From then on, I always make a mark on the motors indicating which pack it came out of, just in case it happens again.