Why does the system alert when "events" such as movement occur outside defined zones?

[ducktape]

I have defined zones of interest, why do I get notification of "Person" detected etc. when movement occurs outside of the zone(s) I have defined.

[JamesC]

While activity zones will limit the number of recordings in your library, motion that occurs outside the zone will still be detected and cause a trigger. For activity zones to work, motion must be detected and analyzed by the cloud to determine whether it occurred within the zone. If the motion was outside the zone, the recording is discarded and will not appear in your library. When your camera is triggered by activity inside or outside the activity zone, this consumes battery life. Repositioning your camera or adjusting sensitivity may be needed to reduce battery consumption.