Smart Home products are all the rage, and have been for the past couple of years, and for good reasons. Forget about the functionality, the usability, or the safety of it for a moment, and simply consider how cool it is to be able to tell a hockey puck sized smart assistant to "lock the door, and turn on the front porch lights" without even having to touch the light switch? It's awesome, and we don't blame any one who gets caught up in the excitement of it all.
Jokes aside, though, this technology is relatively new, and as with most products, the security of the users who are purchasing them often is left on the backburner when they're being developed, and the exploits and vulnerabilities of these products are documented extensively and publicly by enthusiasts and ne'er-do-wells alike. Smart doorbells, smart locks, smart cameras-- you name it, chances are someone has mapped out every major vulnerability that these devices have and pasted it everywhere.
They're still incredibly useful, but until companies making them start taking their product security seriously... you might be better off using a good old fashioned deadbolt and hitting that light switch yourself. If you want to learn more about some of the weaknesses of these products, check out the main article on Sophos Naked Security below.