Great question — answering as the UphillTech team:
According to Netflix they use third parties to locate and hire translaters. In the absence of a common registration scheme and standardized test, how do you find the best resources to do quality media translation? Netflix does this by relying on third parties to source and manage localization efforts for our content. But even this method often lacks the precision needed to drive constant improvement and innovation in the media translation space. Each of these vendors recruit, qualify and measure their subcontractors (translators) differently, so it’s nearly impossible for Netflix to maintain a standard across all of them to ensure constant quality at a reliability and scale we need to...
Full answer by Paulie_D: https://movies.stackexchange.com/a/116801 (CC BY-SA 4.0).
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