The inefficiency isn't the problem, it is a symptom of the real problem, which is lack of trust.
It's been a while since I drove trucks but I recall the absolute worst loads were deliveries to grocery warehouses. Because of DOT Hours of Service restrictions, it sometimes made economic sense to refuse these loads and instead sit idle a day with no work. You had to carefully budget your working hours over a rolling 8-day window and wasting hours at a grocery warehouse kills your earnings for days afterwards.
Grocery warehouses took forever, mostly because of their insistence that I wait while they counted everything and broke down pallets of stuff and re-stacked it. The actual unloading was quick, it was the hours afterwards before they would acknowledge receipt of goods and sign your paperwork to release you. They also used 'lumpers', third-party laborers (who they also did not trust) to count and re-stack correctly so their own employees would have to come double-check everything. Some would expect me to pay the lumpers, which I would always refuse to do, which further delayed things. I think some drivers just paid to get out of there faster.
Contrast this with more sophisticated operations such as a Wal-Mart distribution center where you could drop your loaded trailer and collect an empty one, then leave immediately for your next load. Wal-Mart wasn't worried about under-counted freight or breakage, they are big enough to just declare it unchallenged and the supplier accepts the loss and moves on. Trust doesn't factor into the process.
It wasn't all bad, you could offer to unload yourself for extra pay on some loads, but I only did this very rarely, once when delivering electric cars (GEM cars, like a super-deluxe street legal golf cart) to a warehouse. I drove them out of the trailer onto the loading dock and got paid an extra $100 for about two minutes of work! Easy to count too...