I think the key point is complexity of design.

我想最主要的原因是设计的复杂性。

youdao

As the number and complexity of design patterns increases, the patterns become increasingly difficult to apply.

随着设计模式的数量和复杂程度的增加，模式变得越来越难以应用。

youdao

The enormous complexity of design, particularly of manned spacecraft with their millions of components, requires a high degree of miniaturization and reliability.

设计的高度复杂性，尤其是有人驾驶的有数百万组件构成的航天器，要求高度的小型化和可靠性。

youdao

Most new aircraft experience issues of this sort, an inevitable consequence of a test program becoming a production aircraft and the sheer complexity of modern airliner design.

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However, in terms of design complexity, brand prestige, and price, working with Audemars Piguet is a step up for the Formula 1 legend.

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However, the existence of two different engine designs increases the likelihood of something going wrong either with the basic design or with maintenance procedures because additional complexity is introduced into the fleet.

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