I discovered when I was in my late teens that given a week or two of the same daily alarm, my subconscious would eventually recognize the sound as my alarm and I'd get up, walk across the room, turn it off, go back to sleep and wake up an hour or two later with absolutely no recollection of turning it off. I eventually discovered that using my phone as an alarm, with my call ringtone as the alarm sound, was the only way to trick my brain into forcing me awake: my subconscious has no way of knowing if it's an actual phone call that I need to be awake for or if it's just the alarm, so it forces me awake to figure that out. Its worked for years now.