This is only going to get worse. There are a number of services in Japan that let you pick up part time jobs on short notice. These workers don’t know what they’re doing a lot of the time and their mistakes are going to frustrate customers more.
Edit: A quick search tells me the “training” is some short videos they may or may not watch.
https://www.cbsnews.com/news/ups-drivers-170000-pay-benefits...
The fact that the parent comment cites a short national news story, and crucially fails to distinguish between many specialized kinds of drivers among UPS operations, shows superficial knowledge IMHO.
Amazon here advertises, and this is closer to a literal quote than paraphrasing:
"Need a job? Can pass a background check? Apply today, start tomorrow, no interview required."
So I'm sure their attitude to training is probably "as little as possible".