- It's complicated to create a door lock - It's somewhat complicated to install it on your door - Government can kick your door down - It takes time to turn

- It's complicated to create a door lock - It's somewhat complicated to install it on your door - Government can kick your door down - It takes time to turn the key to open the door - Friendly neighbors can't just hop in whenever they like - Confusion if door is locked or unlocked by looking at it Hmm, let's keep our doors without locks then?