Not as neat, but when I had my small engine shop I had a guy bring in a brand new snowblower that was 10 years old, the engine had failed. It had just a few minutes of running time, and was bright and shiny new. The story behind it was he worked for a dealer and they had a few NOS snowblowers and decided to just dump them so they sold them to employees to $100 each.
Anyway I pulled the engine apart and there was a void in the piston where the wrist pin retainer would be. Someone at the factory shoved a retainer in and assembled the engine. The retain came out and scored the cylinder.
What makes this interesting is B&S warranties the engine from the date of purchase to the consumer. I even took the time to call into B&S to verify, but they warrantied it without one question! The customer was pretty impressed as he expected to pay for it.