In these situations, the scripts for automated test execution need to be changed regularly, which is difficult.

在这些情况下，需要定期地变更用于自动的测试执行的脚本，这是很困难的。

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In software development, this is sometimes made more difficult because, while the fundamental principles are the same for all projects, the tactics (or execution) are modified to specific situations.

在软件开发中，有时候更困难，因为虽然基本的原则对于所有项目都是一样的，但是要根据具体情况修改战术(或执行)。

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If an initiative is in an execution state, it is very difficult — and high risk — to add the burden of process change on top of other challenges.

如果在一个执行区域有了一个新项目，这会非常困难——并且高风险——将项目变革过程中的负担加在其它挑战之上。

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This strategy was simple in conception but heartbreakingly difficult in execution, being based on flawed assumptions, an irreconcilable gap between strategic design and execution, and a comprehensive failure of management information systems.

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