I need one in my home office, one in the main bathroom, and one by the coffee machine and fridge; if I go to these places and leave my phone on the charger, I need the system to still get my attention.
In the office, someone on my team often taps me on the shoulder to remind me we have a meeting. When I'm at home, my phone does that; but if I leave it charging when I use the restroom or get some coffee, it fails. Sometimes I just don't notice the notification pop up, and I don't feel the buzz because it's on the charger instead of my pocket.
I found an Android app that will speak my calendar notifications to me through my phone; that's working well so far. What I might do is collect a few cheap older-model Android phones or tablets, connect them to the Wifi, and just prop them in every room.
So far, I have a Wyze smart watch, and my roommates gave me an Echo, and three Google Home Minis.
I know, I know, I dislike #gafam too. I hate having these devices listening to me; I do not intend to ever speak to them.
But I dislike the alternative more. I get into a state of productive flow that results in missing meetings. Now that I've been working from home for four months, I've entered an almost trance-like state of productivity during the work day. I'm late to meetings too often.