The underlying problem here is a mismatch between the tester's and the developer's mental models of the program; the tester, on the outside looking in, and the developer on the inside looking out.

更深层的问题是，开发者和测试者的思维模式不同。 测试者是由表及里的看问题，而开发者则是自内而外。

youdao

From the outside looking in, it's hard to understand. From the inside looking out, it's hard to explain.

由外向里看，难以理解明白。由里往外看，难以解释清楚。

youdao

Practicing business as usual or looking to reinvent your firm from the inside out, looking within for the answers rather than chasing technology as the cure all for your woes?

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Of course motorists spend most of their time inside the car looking out, not the other way around, and the 2012 Acura TL remains rewarding in this regard.

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Filming with an unflinching biomorphic intimacy, as if looking at the body, inside and out, through a microscope, Carruth quickly leapfrogs over the grotesque and into the transcendent.

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