Final answer:
The statement is false; as engineering/design completion increases, the accuracy of estimates typically improves, contrary to the notion that it decreases. As design details are refined, the information available allows for more precise and reliable estimates.
Step-by-step explanation:
The statement 'as the percentage of engineering/design complete increases, the accuracy of estimates begin to decrease' is false. In project management and engineering, the accuracy of cost and work estimates generally improves as the project progresses and more detailed information becomes available. This progression is often represented as a project moves through different stages, from conceptual design to detailed engineering. For instance, the initial conceptual design estimates are rough and have a wide range of potential variance. As the design becomes more detailed, these estimates become more precise and the range of variance narrows. This concept is aligned with common practices in engineering, such as using various levels of project definition to improve the reliability and accuracy of project estimates.
Referring to the provided references, it's clear that as the accuracy of measurements and calculations increases, which tends to happen as design/engineering work progresses and more information becomes available, the estimated values become more reliable. This contributes to a lower percent error and higher accuracy. However, it is important to notice that estimates are inherently associated with some level of uncertainty and the goal is to reduce this uncertainty as much as possible as the project details get finalized.