Amazon refurb process and factory reset?

[bulltricks]

Does anyone have insight into the mechanism is that the Amazon in-house team uses to "refurbish" devices?

Why?

Amazon's mediatek/USB-C devices don't exhibit the typical Mediatek bootloader during power-on.

If, hypothetically, the factory reset mechanism is "broken" before the device exposes the gadget file-system, is the device considered bricked and written off?

Or is there an non-obvious mechanism which allows authorized access?

thanks in advance, and speculation is welcomed.