There's another part of this that I guess I should say, aside from that I wouldn't say fire if there's no fire. Since this is the internet... but it's the fake internet... I thought I would share the less intelligent version of the reason. -Because you're causing panic and wasting people's time. But... there's also an intelligent version of the reason that I could add into this aside from communism. If someone said that there were a fire somewhere, and there were a real fire somewhere else, people would try to pour water on the first problem they heard, well, they'd bring water and lose time. What would happen to the real fire? It would just get worse, because people reached it later, and it would be more difficult to put it out, because they were distracted somewhere else, which wasted their time, but if there were another type of problem, one fake and one real somewhere else, also made it more difficult to stop because it got worse.