It's at least mostly going away nowadays, but....pulling a fire alarm will not make your school fire sprinklers go off. Getting one sprinkler to go off is just that. One sprinkler. None of the rest will go off.

Also, fires in a building are never a spot here, a spot there, over there a spot, and just randomly burning patches all over the place. It just grows out and up from its origin point, for the most part. It doesn't magically plant little patches all over the place. It's also often times so smoky and so thick with smoke that you quite literally couldn't see a big portion of fire if it were ten feet in front of you. You feel the heat and maybe see a faint bit of orange glow. Sometimes you don't even get to see that.