If your spark plug preignition damage.
This is a serious condition that will show up as a side electrode that has been burned away.
This indicates running too hot due to not enough fuel being present in the mixture or in the combustion chamber.
This type of problem can be caused by performance upgrades that alter your engine’s recommended plug heat range, such as high-output ignition, coils, exhausts, or cams.
Have your fuel injection and timing checked immediately before your plug falls apart, and consider using a spark plug with a lower heat range.