Critically, it also get packed at their schedule.

Renting containers and keeping them on your property (vs. at the other extreme Singapore) is cheap, so you can do whatever makes sense, pack one in hours, days or weeks. No need for fine grained rush, rush efforts at a crowded port (the need for high utilization of expensive cargo ships and terminals does ensure that all moves quickly, and e.g. killed off some historic ports that were somewhat inland on a river, the cargo ships didn't want to take the extra time to transit it).

And a lot less pilferage. Scotch whisky distillers were some of the earliest adopters of the container system according to The Box.