When a
software developer explains why the
application (formally known as, 'teh codes') acts in a certain way that is surprising to the non-technical user.
Often the engineer will
accidentally come off as arrogant or boorish. This may be to compensate for the fact they are trying to pass off a bug as intended behavior.... or that they are just as confused by this behavior as the end-user.
parallel to mansplaining or mansplain