Here's how #surveillance works:

Watch what is normal to learn what is not normal.

"But my life is boring! I've nothing to hide!"

If someone sees enough of your boring days, they can easily tell when your day isn't boring to you. Perhaps because you're up to something?

If someone can learn what a boring day looks like for the typical person, they can easily spot the person not having a boring day. Perhaps that person is up to something?