You return to the state as the system was when you burnt the image. That is a lot better than factory state (unless your system is defunct) because you do not have to deal with a lot of updates. Last time I did a reinstall (Vista), I had to deal with 300 updates. Took 3 days that orgie. A recovery from an image takes 30 minutes. And you do not have to reinstall any programs or redo any of your tweaks and settings.