Also, seeing as many nations offer rewards to police for confiscations, asking local police to hold off on a known shipment is like asking to them to restrain themselves from scooping up money floating by on a stream, seriously affecting their willingness to cooperate.
而且各國都有緝毒獎金，有時要某一國警方監控卻又不准動手，等於是限制對方撈取過門的油水，也會影響合作意願。