That's not the way a security system should work, it should "fail secure" and not let anyone in that it can't verify 100%. There are lots of reasons to lock al

That's not the way a security system should work, it should "fail secure" and not let anyone in that it can't verify 100%. There are lots of reasons to lock all of the doors, or even lock out a single person. And, since such systems can fail frequently, there always needs to be a backup plan in place, almost always involving humans.