Newsworthiness

What is newsworthiness?  How do people know when news is worth telling or not?  I relate this to even telling a simple story.  I always tell stories that might not be the best and then I think about it...what was I thinking??  It all comes down to this, do people care about it?  I think that point is the most important.  Obviously, selling the story is very important, but I think that the human interest aspect of it is the most effective.  Also, video helps as well.  It will allow more of an interest with video, but again, the most important is the story.