You know what's even more annoying? You can set a notification or email reminder to go off prior to a calendar appointment, but can't set an alarm to go off prior to one. I need my phone to make noise when it's time for me to get ready, not just show a notification!
Notifications have a lower level of priority than an alarm. Notification volume is set differently than alarm volume. Alarms take over the screen whereas notifications just give you a prompt at the top. As a person with ADD, it's a huge inconvenience and I need to use workarounds that are unreliable. I just want a ducking alarm when I need it without getting some stupid artificial limitation on why I can't do it.
I have the same problem as the person above and for me at least, my phone is always on silent. I use a smart watch and only select priority notifications go to it, anything else, I'll just see it when I next pick up my phone. A notification, even if it's sent to my watch, I might miss, but an alarm will always make noise, vibration, basically will get my attention for sure. So for people like me and I'm guessing the commenter above, grue, who are trying to minimize the ways our devices distract us, notifications aren't gonna cut it when I want an alarm for something important.