Yep, there is an interesting book "Poorly made in china" talking about the same thing... not powerbanks but same modus operandi.
For example (hope I didn't mess up the details, it's been some time since I read it), a cosmetics manufacturer vendor replaced shampoo bottles with ones made with less (thinner) plastics multiple times, untill they started being destroyed in shipping... without notifying the company that ordered the shampoo... and then wanted more money for the "better" shampoo bottles.
Also some very questionable practices:
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The hair gel that we produced at the factory was green. One day, I noticed that the worker who filled the gel bottles had a skin condition. His hands were covered with the slick formula, and beneath the green, shimmery layer, I could see that the skin on his hands was peeling. Small, raw patches of flesh were exposed, and you didn’t have to be a dermatologist to see that his skin was infected.
“We should probably do something about this one,” I said to Sister, trying to sound calm, while in my head alarm bells were ringing.
Sister did not see the point. “Why?” she asked.
“It might be a health issue?”
“But the worker has done nothing wrong. It’s just an allergic reaction.”
Trying to press the matter, I suggested that the worker might contaminate the product.
Sister twisted around the argument. “How can he harm the product when it was the product that caused him the harm?”
For example (hope I didn't mess up the details, it's been some time since I read it), a cosmetics manufacturer vendor replaced shampoo bottles with ones made with less (thinner) plastics multiple times, untill they started being destroyed in shipping... without notifying the company that ordered the shampoo... and then wanted more money for the "better" shampoo bottles.
Also some very questionable practices:
-----
The hair gel that we produced at the factory was green. One day, I noticed that the worker who filled the gel bottles had a skin condition. His hands were covered with the slick formula, and beneath the green, shimmery layer, I could see that the skin on his hands was peeling. Small, raw patches of flesh were exposed, and you didn’t have to be a dermatologist to see that his skin was infected.
“We should probably do something about this one,” I said to Sister, trying to sound calm, while in my head alarm bells were ringing.
Sister did not see the point. “Why?” she asked.
“It might be a health issue?”
“But the worker has done nothing wrong. It’s just an allergic reaction.”
Trying to press the matter, I suggested that the worker might contaminate the product.
Sister twisted around the argument. “How can he harm the product when it was the product that caused him the harm?”