I'm always skeptical when someone says their alarm didn't go off, especially when it's me. I usually assume I slept through it.
This morning though I have absolute confirmation that there is an issue with the alarms on the Forerunner 235.
I have a weekday alarm for 5:10 that is basically always on. This morning I woke about 20 minutes early, so when 5:10 hit I was awake and sitting in my recliner watching local news.
So there is this quirk with the 235 where sometimes it will stay on on the Bluetooth, HRM, steps, etc... screen and not timeout and go back to the watch face. This is actually a "feature" that some have requested that seems to happen for me when I cycle through screens while the watch is charging.
Anyway, this morning played out like this.
1. I woke around 4:50
2. Around 5:00 I forced a sync on my watch.
3. After the sync, my watch stayed on the Bluetooth screen instead of returning to the watch face.
4. At 5:10 the alarm DID NOT FIRE as it should.
5. Around 5:12 I verified that my 5:10 alarm was on and the time on my watch is correct.
So somehow whatever causes the 525 to sometimes stay on a non-watch-face screen also prevents the alarms from going off.