I encountered this kind of inconsistency with my Android phone, too (Samsung Galaxy S22). I think every time my alarm failed to go off it was because the phone had automatically updated its OS and restarted overnight, and background apps like the alarm wouldn't run until I entered my pin to finalize the phone's startup process.
I've usually used my $3-4 alarm clock for waking me up in the morning, and then my phone timer for naps.
Now that I just took a closer look, I was able to find a way to disable automatic updates on the phone. (I had to find and tap "Software update > System Update Preferences > Smart Update" in the Settings app.) But I like the alarm clock, so I'll probably keep using it anyway. Better that my phone isn't the first thing I interact with every day.
One thing that Apple has got right with the iphone is: every time it's installed an update over night, restarted, and is waiting for me to enter my PIN to unlock it, the alarm still worked.
Same here, switched to a physical alarm clock after inconsistent alarm behavior post OS updates on my Samsung S22.
I disabled Smart Update after reading your post but considering my phone used to prompt me to update, then started doing them on its own - I wouldn't trust that setting to stick.
I have S22 but don't use alarms much. However, my wife has S23, and this very issue is something I've been banging my head on just last week! Her alarm clock would occasionally not ring, but instead the phone would give a few beeps. My wife has a bunch of stacked alarms in 10 to 30 minute intervals, and I've listened to all of them going "beep beep beep <dead>".
I don't know what's going on there; I've read hints that for some people, their phone thinks it's in a call, and manifest such behavior in that situation. Some reports blame Facebook Messenger. What I know for sure is that it isn't restart or update related.
And yes, it's beyond ridiculous for this to be happening in the first place. It might just become a poster child of how idiotic tech has become. For the past decade or so, it feels that each generation of hardware and software, across the board, is just fucking things up more - even things you thought were so simple and well-understood you couldn't possibly fuck them up, like alarms or calculator apps.
Time zones. I've had trouble while traveling when my phone decides to change time zone, shifting the alarm times unrequested ways. I would appreciate a phone that could properly understand GMT in a way that would allow me to set an alarm at a specific GMT time regardless of which timezone I step into. (yes, I am sure there are XYZ apps that can do this, but I don't see why the base OS cannot handle this without installing more apps.)
One problem with Android phones is that they're all different, sometimes greatly so, because the different phone vendors customize them with their own software, much of which is utter garbage. The stock alarm app on mine has never failed me either, but with some other phone, who knows?
I've usually used my $3-4 alarm clock for waking me up in the morning, and then my phone timer for naps.
Now that I just took a closer look, I was able to find a way to disable automatic updates on the phone. (I had to find and tap "Software update > System Update Preferences > Smart Update" in the Settings app.) But I like the alarm clock, so I'll probably keep using it anyway. Better that my phone isn't the first thing I interact with every day.