Bookmarks

I've found a bookmark on the 86th page of one of the greatest books i have ever read. Was this the last page the previous owner turned? Marking the next chapter for him or her to come back to before losing the book? Was the book not quite the flavor the expected? Or was this simply the chapter the loved the most and upon finishing the book, chose to mark it for the next one whose path this book may lie in? Or perhaps it is just another piece of paper in a book, trapped between two pages. Lost. Forever.