Why are some couriers received by SMS verification code and some quick drops sent directly?

Why do some couriers pick up the pieces by SMS verification code, and some send them directly? . .

The short message code belongs to the self-contained cabinet (express delivery). Because the courier first puts the delivered express mail into the self-reporting cabinet, and then sends a short message to inform the recipient, who opens the self-reporting cabinet to pick up the piece, and there is a verification code in the short message.

Send it directly to the courier. If there is no self-contained cabinet or the goods are too big to put in the self-contained cabinet, the courier will call to inform the delivery.