Final answer:
In project management, accuracy increases with progression through project phases, while costs also rise due to higher expenditure on resources and labor. Similarly, in economics, average and marginal cost curves are U-shaped due to economies of scale and diminishing returns, resulting in costs increasing after a certain output level.
Step-by-step explanation:
In project management, the general trend regarding accuracy and cost as a project progresses through its phases is that accuracy tends to increase while costs also increase. This means that as the project moves forward from initial concept and planning stages into execution and closure, the team's ability to estimate project outcomes and requirements becomes tighter and more precise. However, during the same progression, the project incurs more costs, initially starting with design and planning expenses and then moving on to the costs of resources, labor, and other expenditures necessary to carry out the project.
Why do costs increase as more output is produced? In line with economic principles, average and marginal cost curves exhibit a U-shaped trend for a reason. Initially, costs decrease due to economies of scale, as fixed costs are spread over more units of output. However, as production continues to increase, diminishing returns take effect, and the cost to produce each additional unit starts to increase, leading to the upward slope of the cost curve.