If this is correct, then it would not be surprising if a few warehouses are outliers even if the overall figures are reasonable. After all, randomness (both in terms of overall luck, and the distribution of shitty managers) will end up skewing a few of the results very high or very low.
The places with the longest living and happiest people are rural towns.
The places with the shortest living, most stressed people are also rural towns.
Small numbers breed statistical anomalies because it’s easier for 10 people in a town of 100 to happen to have bad or great lives than it is for 10000 of 100000.
Amazon has sort centers, distribution centers, returns processing centers, robotic fulfillment centers, non-robotic fulfillment centers, and maybe other stuff I don't know about.
The people at different warehouse types are often doing different jobs.
According to a quick search, JFK8 is fulfillment center where they do pick and pack, and it's also one of the warehouses with the Kiva robots.
Couldn't find too much about PDX9.
Alternatively is it still a large one? They have large hubs that serve larger areas, not everything is around to be serviced by a local hub.
https://www.google.com/maps/place/Amazon+Fulfillment+Center+...
Maybe this issue is specific to certain locations, markets, or segments of the logistics chain. I'd imagine that employee turnover, the products being shipped, the tasks being performed, and product volume varies significantly based on the particular location. They have a lot of facilities doing a lot of different things. The media usually mentions 'fulfillment' specifically with these articles, but that's only one part of their logistics operations.