If your project has only a few tasks that need to be done in a hurry, you can probably manage it by listing the tasks in rough chronological order. It doesn’t matter much if two or more tasks constitute a substep within the project; your main concern is that all the tasks get done as soon as possible.
If, however, your project contains dozens, hundreds, or even thousands of tasks, then trying to accomplish everything in your project all at once would be like trying to jump to the top of a tall tower in a single bound (crash!). Tasks, phases, and milestones are like the steps leading to the tower pinnacle. They enable you to get from the start to the finish of your project, one manageable chunk at a time.
