I think you might find that you continually refine/redefine your purpose as you go through the PhotoReading steps. When you first get a book into your hands, you generally have some purpose for reading it, correct? Either general knowledge about the subject, specific knowledge about the subject, the need to write a paper on the subject, etc. The initial purpose might be a little vague - that's OK. When you preview the book and get an idea of the structure of it, as well as more of what it's about, you can refine or redefine your purpose...or you might discover that the book does not meet your purpose (in which case you might put it aside). Then you can PhotoRead the book and, if you want, immediately mind probe and perhaps narrow your purpose down even further.

None of the steps in PhotoReading are cast in stone, nor do they "turn off" once you are past them. You are dynamically interacting with the text, awakening your mind and actively seeking the information that you want from the book. Think of the "left brain" parts of PhotoReading as helping to direct the resources of your inner mind as to how they are to process and package the information for you, the "right brain" then absorbs and sorts the data and makes the neural connections, then the two work in tandem to bring to your conscious awareness what you've read, in a format appropriate for you, and focused on what you desired to know. If you aren't active in PhotoReading I think you will have difficulties in getting the successes that you want.