That’s why rule machine exists. If you are an advanced user with a very specific need, you can do pretty much whatever you want with it.
Adding too many features and options to other built-in apps could easily overwhelm some users.
HSM is intended to replicate the functions of more traditional security systems. I have never had a “real” home security system. Is it common for them to allow alarm triggers from the flip of a switch?
A) a worthy use case that is not at all a "one off" expectation for HA,,
and
B) the casual user having to roll up their sleeves and go beyond what's provided as a baseline in the environment.
I get that embellishment of the tool kit takes precious time and indeed causes wonder where best to do what the longer one uses/implements a system around this box. The terms just need to be clear to folks buying in.
While the marketing does not in any way deceive, it is easy for new folk to assume stuff and later find themselves going..."oh, I can't do that in there, I must go over there, or I must do a little here and a little over there...and oh, make sure it still does what I want after every environment upgrades (which one really hates to be left behind).
I have a lot of respect for the accomplishments in this box, and the small staff that got it to this point. No need to argue any of the above, I'm about converted... but I'm still willing to say things like this before the kool-aid has taken full effect.
How the heck can anything this complex and subtle ever be communicated, other than in the context of someone who spends some time here in the community reading and learning? It is, no doubt, a complex thing, this hub. It's capable of a great deal, can support a wide range of very custom automations. Yet, at the same time, we endeavor to make it accessible to new users, with apps like Basic Rule, a new getting started approach coming in the 2.3.1 release, etc. We're all ears about requests for features, and we add many that are suggested here. That doesn't mean the every request will be or should be fulfilled.
The point is that we can't possibly meet every use case in a single app like HSM. And, one principal of home automation is "your use case is not my use case". So an app like HSM quickly becomes a slippery slope of feature creep. You probably have a perfectly reasonable use case, but so do others have one that is different from yours, and before very long, HSM turns into RM. Now, there are features that do get added from time to time, ones that obviously fit into the clear purpose and design (e.g., shutting off a valve on a water leak).
As I said before:
Who knows, maybe your use case is compelling enough to drive a new feature.
Also, there is another way to do this right now: There is an app in our public repo that changes a contact sensor into a motion sensor. That app could be easily changed to turn a switch into a contact sensor (or whatever type of sensor), and the resulting sensor could be used in HSM to trigger it. No RM involved, all of you security system within HSM.
Try this: The app will create a virtual contact sensor with the name you give the app. When the selected switch turns on, the contact opens; when the switch turns off, the contact closes.
I understand why the decision was made to keep HSM streamlined. I haven't bothered with it until recently due to perceived level of complication. It wasn't nearly as difficult as I thought it would be. I think part of the problem or fear I faced was the complete lack of hardware for what I wanted to do. I spent months trying to find a zigbee siren... No luck. Finally landed on a simple siren that goes off once it's powered and wired it to a sonoff s31 lite. Total cost 20 dollars.
Slightly off topic... but not since it deals with the standard capabilities of HSM (which I too started out wanting to give an increasing role in the basic functions of my home security).
Will be curious how that siren gets turned off/reset, just through HSM, to avoid driving your neighbors crazy when it gets turned on by some (most likely false / non-cricitcal) trigger circumstance.... while you are in the middle of something offsite, or on a plane, and can't get to your phone to see the notification and deal with it.
Having some configurable automatic reset of alarms (and alerts like sirens) either after a duration of time and/or the triggering device resetting itself to the a non-triggering state...is a common option in Security Monitors.
That's one of the reasons I keep believing it should be an obvious & available step while configuring things WITHIN HSM.
(He says with all due respect to those that built-the-beast that isn't a full-fledged-security-system but MAY increasingly be used as such by "Easy-Button-HE" buyers.)
Here's a simple use case. I have a real security system: abode. I use their door sensors for some things that i don't want to trip a monitored alarm.
I'm using the abode app in HE to access those sensors and output the events as virtual switches. It would be ideal if there was a virtual open close sensor that would show up on hsm, but that kind of virtual device doesn't exist. So next best thing would be using a virtual switch.