[m10i]

> A thief doesn't know if there's a doorbell camera on a particular home until they're already on the porch and recorded.

When a thief wants to steal something, they usually stop trying to steal that thing once they become aware they are being monitored. Even if they only realized once they reached the porch.

It's not a guarantee, but it's something. And it provides a trail to follow if something is stolen (or worse).