Imagine if you will...
The locksmith unlocks your door while you are asleep. But you have the security chain lock enabled. So the contortionist eases her way through the space in the door. Now she has access to your home. She is armed and lets the locksmith in. The locksmith is also armed and has training in mixed martial arts. You have a gun though but it's in the lock box or way up in the closet. Yep the criminals don't care.