This format is very common in long form journalism. New Yorker articles are a good example of this format. First they have the hook, then they go back and tell

This format is very common in long form journalism. New Yorker articles are a good example of this format. First they have the hook, then they go back and tell the persons entire life story. I think the point is for you to get somewhat emotionally invested in the story, almost like reading a novel or short story instead of just reporting the facts. Some people find it more enjoyable to read, or may find it easier to retain information in this format as you begin to get invested in the story.