This is because our services allows 10 sensors to be monitored for normal activity.
This means that you can see doors opening and closing in real time on those 10 devices when the system is disarmed.
This does not affect your sensors when armed for Stay or Away as those will always report in, even if you have more than 10. This is just for "activity" monitoring at all times (ie. when unarmed too) for those particular sensors. This might be something like a liquor cabinet, safe or gun cabinet sensor that you want monitored even when the system is unarmed.
If you have more than 10 liquor cabinets, safes and gun cabinets, well...that's a whole different issue. :)