Because internal quality and external quality are not the same things.

因为内部质量和外部质量并不是一回事儿。

youdao

providing an external quality assurance programme and reference testing service and supplies to laboratories;

向实验室提供外部质量保障计划和基准监测服务与器材；

youdao

He makes this distinction to note that while external quality can be lowered to shorten time-to-market, internal quality cannot.

他这样加以区分，是为了说明想缩短市场投放时间，可以降低外部质量，但是决不能降低内部质量。

youdao

But once they are through that, external quality control ends.

ECONOMIST: Chile

Because our patients are not able to evaluate the quality of their care and external quality metrics are so poor, I wonder if the time might be right to introduce real supervision into medical practice.

FORBES: Guest Post: Is It The Right Time To Introduce Real Supervision Into Medical Practice?

Instead, an external high quality dual-microphone array comes standard with this card.

ENGADGET: Creative reveals Sound Blaster ZxR, Zx, and Z PCI-Express sound cards, pumps up the volume