1: Is it interesting?
This is perhaps the most important criterion. If it's not interesting, why tell it? Your story should make the viewer, listener or reader stop in their tracks, look up from their breakfast, and want to tell the story to someone else. A good test here is if one of your colleagues says "so what?" - if you can't answer that question, then it might not be quite the story you thought it was.
2: Did you know about it before?
If you consume news voraciously, you'll know if your story is fresh and original. Someone in your newsroom will have a fantastic memory for every story that's ever been done. If they haven't heard the story before, the chances are it is new.
3: Does someone want to keep it quiet?
If after you've done all your preparatory research and interviews, and the main interviewee avoids taking your calls or does not answer your questions, it's likely that the person has something to fear about your story or has something to hide.
4: How many people will it affect?
It might be the greatest story in the world, but it may only affect one person. That would not rule out telling the story, but the more people your story affects, the more likely it is to be of interest to your audience.
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