许多项目失败的原因正是因为需求渐变，而项目经理需要勤快些，对此加以防范。

Many projects fail because of scope creep, and the project manager needs to be diligent in guarding against it.

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项目管理中的范围渐变(也称为需求渐变)是指项目范围的无控制更改。

Scope creep (also called requirement creep) in project management refers to uncontrolled changes in a project's scope.

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