The questions aren't complicated. Some are personal, like your missions, inspirations, fears, etc. Some are fun like what song is stuck in your head or what book you're reading. What they do is paint a picture of your life day by day. Then you start over. By the time the journal is done, you have a document of the last five years of your life viewed daily through the mundane, as well as the metaphysical.
The best part of this journal is that it allows you to see yourself grow and change as a person. I also love that the questions are easy and there isn't a ton of space, so you aren't supposed to write lengthy posts. It won't ever be a chore to work on the journal, keeping the energy you will have going into it alive hopefully.
For people who like to keep track of things, this is a nice way to look back at your year and it's also a compact time capsule. If you're the type to save a lot of items to maintain some hold on your memories, this eliminates some of that space. Because you're answering daily, it's a record of five full years in one small book. With the guided questions, it's also different than a diary. It is easier, because you're not staring at a blank page when you have nothing interesting to say about your life. You can still keep a diary elsewhere, but this is a nice quick thing to do each day. Keep it on the nightstand or on an end table by the couch, take a couple minutes daily, and it's done.