The increasing level of automation and technology that has been implemented by the average local courier service should mean that you no longer have to give directions to your courier driver. This of course is not a blanket statement, and mostly refers to the giving of road directions. It is still often encouraged, and necessary to provide drivers with directions such as how to find a particular office number within a given building, or on which unit to make a delivery to. However, if you order a courier, you should be able to in the cases of a good full service courier simply be able to give them a pickup and delivery address and not have to give any further directions than that.
The reason that no reputable courier service should need to get directions from you personally anymore has to do with the integration of GPS technology into most couriers operations. Almost every courier will now carry a Smartphone or a separate GPS unit that has the capability to map out the most efficient route for them to make their delivery.
Also, if the local courier service is making a planned delivery run, their dispatch software may plan out the most expedient route for them to make all their pickups and deliveries on their GPS based on the dispatches that have come in on that given day. The fact is that unless you order point to point delivery service, your driver will likely be making other stops along his way, so your directions are not going to count for too much. Instead, the software the company uses to manage their dispatches, will, in the best cases, automatically upload route information to a GPS unit providing them with their directions for the day at the touch of a button.
Obviously this is not a hard and fast rule, and if you want to give directions to your regular courier service driver because you want them to take a faster route, by all means feel free to offer your advice. However, if a company or a driver is asking you for directions it may indicate to you that they haven't updated to a GPS system in their operations yet. This lack can make them less reliable and less timely in their deliveries than the competition, so their lack of those features may be something you want to consider when thinking about hiring a courier on a long term basis.