There are different kinds of publications or presentations; some are for pleasure or entertainment (example: novels) and others are for guidance (example: How to get more from anything you read, watch, or listen to).
Reading for pleasure is truly fun, and you just can’t wait to quickly get it through so as to move on to the next and thus have more fun! And that’s okay. On the other hand, when you determine that a publication is for guidance, you need to bring a totally different attitude to it, and that includes having to read it more than once; unless you don’t care enough to want to truly get the import of what you’re being guided on.
It is simply the case that you never get everything in a single reading, and that, going over a presentation of any sort reveals more to you; it is just the way it works. In most cases, up to seven readings is perfect; in extreme cases you may have to go over up to twenty-one times in order to satisfy yourself fully that you have truly grasped or understood everything!
NB: This has been presented with reading in focus just to avoid too many inflexions, but the principle applies solidly to watching or listening to a presentation as well; be it seminar, audio or video, etc. Repetition works magic!