The correct answer to this open question is the following.
Although the question doesn't provide options or further references, we can say the following.
The commander and his staff must work to clearly display objectives and end states by phase, demonstrating explicitly their incorporation of the elements of design in joint operations.
Design and planning are two important components of joint operations. Commanders have to identify the problem to solve it in the best way possible. They have to create the best approach and establishing an effective plan. This, of course, takes time, but Commanders have to be prepared in critical times or crises, when time is a factor, to swiftly react and design the proper plan to act immediately until the situation is under control.