In the course of planning your presentation, you need to have that goal before you at all times. It becomes the standard by which you measure all your other actions, ensuring that you don’t deviate from the goal. Without keeping that goal before you, it’s very easy to become bogged down in details that shouldn’t be part of your presentation. Instead of providing necessary information, it is easy to get sidetracked, giving a bunch of information that doesn’t bear on the decision at hand.