Which of the following indicates that a contractor may struggle due to unqualified labor?

The indication that a contractor may struggle due to unqualified labor is reflected through higher project costs. When unqualified labor is utilized, it often leads to inefficiencies and the need for rework or corrections, which in turn increases costs. The lack of skilled workers can result in mistakes that require additional labor hours or materials to fix, driving up the overall expenses associated with the project. Contractors may also have to invest more resources into supervising unqualified labor or hiring additional qualified labor to compensate for the shortcomings, further contributing to increased costs.

On the other hand, the other choices do not align with the premise of struggling contractors due to unqualified labor. For instance, lower quality materials may reduce costs initially, but they could be a separate issue not directly tied to labor qualifications. Increased worker satisfaction typically indicates a positive work environment, which would not correlate with unqualified labor. Lastly, reduced project timelines would generally signal efficiency rather than difficulties arising from inadequate labor, as unqualified labor often leads to delays rather than expedited timelines.