Small block Mopar 2.05 and 2.08 valves.

I’ve been running the stock Edelbrock exhaust valves for years with zero issues probably because of their weight. But we did have a 1/4 inch piece of a stock Edelbrock intake valve break off on number 3 and lodge in a piston on number 6.
How was it running in the two or three passes before that happened? Any warning signs at all?