I think it all boils down to an intentional drop versus an accidental drop. An accidental drop cannot be careful whereas an intentional drop requires care of forethought, whether the end aim is to break the object or not.
Exactly that - it's that horrible blue stuff which is so toxic that in the event of a single drop making contact with your anus, it can seal her shut in an agonising mass of bubbling, melting flesh. Ah yes, the old tactical toot. Priceless when trying to end a meeting that's dragging on.
They are ace unless one's efforts to stifle the noise are futile (dependent upon the crowd at the meeting, of course).
...like if Michael Jackson's hands had slipped that one time on the balcony. That would have been a careless drop.