I used to leave my door unlocked and then I read this story on crimelibrary about this guy who would go around neighborhoods rattling door knobs and if the door was unlocked he would come in, kill whoever was there and eat their brain. That's right, eat their brain. Now I keep my door locked and if someone leaves it unlocked I say Do you want your brain eaten?!!?
Ratatouille Red Riding Hood Story Book Rapunzel Story Book Red Handkerchief
The better extinguishers can be taken in and recharged for a small fee. Also it should be taken down and given a good shake once in awhile as the powder tends to settle and not come out as well.