Confused about why to use Sense linked to camera?

Love my Wyzecam but am confused and could use some real life examples for Sense.

If my Wyzecam records and sends alert when activity is detected, expscially if settign up zones, then where is the additional functionality to have a contact sensor or motion sensor activating the record and alert. Unless you want the camera recording in a different location than the contact sensor ?

I’ve got 3 cams, on pointed at my front door hallway, one out my patio door, and one at my walkway in my front yard. Each will alert me already when there is activity in the area. I’m sure i’m missing something obvious.

check here and here for some ideas discussed already.

more examples from wyze themselves https://www.youtube.com/watch?v=aqSwky86P7A&list=WL&index=24

Thanks, I should have searched first