Why start at low power objective?
You start at a low power objective because it gives you a broad view of the slide. Think of low power as looking at the world, the next power at a country, and the next a state. If you started on the state level you would be too far in to be able to scan for the specific state you are looking for. A low power allows you to scan an large area for what you are looking for rather that going slowly from small area to small area.
