Which statement best describes the effect of changes on the critical path?

Which statement best describes the effect of changes on the critical path?

• A. The total project length is unaffected by changes on the critical path.
• B. If any task on the critical path increases, the total project length increases.
• C. Any change on the critical path reduces the project duration.
• D. The critical path governs only costs, not schedule.

Answer: (B)

The critical path is the longest sequence of dependent tasks in the project network and it sets the minimum possible project duration. Any increase in the duration of a task on that path will push the finish date later, because there’s no slack to absorb that delay. So if any task on the critical path takes longer, the total project length increases. Changes on non-critical tasks may not affect the finish date unless they consume slack and shift the critical path. The idea that the critical path only concerns costs or that it would reduce duration with any change is incorrect; it governs schedule, not cost, and increasing durations on it lengthens the project unless you shorten those tasks (which is a different scenario).

The critical path is the longest sequence of dependent tasks in the project network and it sets the minimum possible project duration. Any increase in the duration of a task on that path will push the finish date later, because there’s no slack to absorb that delay. So if any task on the critical path takes longer, the total project length increases. Changes on non-critical tasks may not affect the finish date unless they consume slack and shift the critical path. The idea that the critical path only concerns costs or that it would reduce duration with any change is incorrect; it governs schedule, not cost, and increasing durations on it lengthens the project unless you shorten those tasks (which is a different scenario).