joshua was having a difficult time meeting that improved schedules and budget what might be the most likely cause

There was a lack of clarity and expectations in the original work plan goals.

Explanation:

When creating a work plan , expectations refers to a realistic set of goal that an organization hope to achieve after implementing the work plan into their operation.

Expectation is very important for the decision maker in determining a couple of things, such as;

- The time needed for the plan to show result. (which will influence things such as meting schedule, determining deadline, etc)

- The amount of resources and workhours that the company need to invest into the plan (which will influence the way budget is designed)

- The standard that should be use to measure company's performance.

c.

clarify customers’ doubts only when asked.