Because it's been fun to create discussion type videos on my books, it's led me to think of several aspects to doing this. I can see value in doing one before a book is even written as it really does cause the writer to stop and think-- what is my book really about? Not so much the plot but the underlying message.
Here's one I did for my book, Hidden Pearl as it looks at the meaning of a pearl as the underlying message in this story.
It's not that the meaning is new to me but learning to express it more succinctly might be helpful from a marketing standpoint where people are in a hurry and won't give you more than a moment or two or three if you are lucky.
In terms of creative inspiration, I think I will do one for the book I hope to start probably in mid-August-- not to share with others, of course but just to see how it goes and how it compares later when the book is finished whether my message changes with the writing. Sometimes as you get into a story, you see the deeper purpose in writing it.