> Summary: Certain (not all) Amazon warehouses seem to have per-employee injury rates that are significantly higher than the industry average, as in twice as high or more. Apparent reason: It’s not they’re actually dangerous places to work, it’s just that they’ve maximized efficiency and reduced waste to the point where people are picking and packing and shipping every minute they’re working, never stopping. And a certain proportion of human bodies simply can’t manage that. They break down under pressure.
Wouldn’t a more parsimonious explanation be that the job previously consisted of a safe part and a dangerous part, and it was easier to automate the safe part, so now more of a human's time on the job is spent doing the dangerous part?
If you imagine the "safe part" of the job as "slack" (i.e. imagine that the employees were previously half working, and half doing nothing—not that they actually were, but it makes the model clearer), then they've effectively just gotten rid of all the slack, and so made the employees do twice as much work per work day. If there's a constant small probability of injury per item packed, then of course doing twice as much work per work day, will lead to twice as many injuries per employee per work day. You'd have gotten the same number of employee-injuries out per items-packed in, no matter what time scale that packing occurred on.
Wouldn’t a more parsimonious explanation be that the job previously consisted of a safe part and a dangerous part, and it was easier to automate the safe part, so now more of a human's time on the job is spent doing the dangerous part?
If you imagine the "safe part" of the job as "slack" (i.e. imagine that the employees were previously half working, and half doing nothing—not that they actually were, but it makes the model clearer), then they've effectively just gotten rid of all the slack, and so made the employees do twice as much work per work day. If there's a constant small probability of injury per item packed, then of course doing twice as much work per work day, will lead to twice as many injuries per employee per work day. You'd have gotten the same number of employee-injuries out per items-packed in, no matter what time scale that packing occurred on.