Badly planned flights should not happen. Pilots who don't carefully plan their flights end up dead quickly. Lack of fuel is one of the easier to handle things that can go wrong from bad flight planning.
The pilots took exactly enough fuel to reach their destination. They didn't have enough fuel to divert to an alternative airport. They didn't even have the mandatory 30min of reserve fuel. They did not account for a minor holding pattern just before landing (ironically, because another plane had a fuel leak).
The crew failed to declare a fuel emergency, and crashed 18km from the airport. They had only been in the hold for 10 min when their engines ran out.. they were very short of fuel, the pilots knew they were short. They should have diverted (or declared a fuel emergency) almost an hour earlier, but they didn't want anyone to know how close they were cutting it.
My dad dreamed of being a pilot and when I was a kid he subscribed to the flying magazine (or something like that I don't remember that name.) every single issue had the last story being "I learned about flying from that" and nearly every single one was a case of bad planning, usually a case of flying into bad weather because of the bad planning.
