Does it fail to wake you up, or do you get up, turn it off, and go back to sleep. This is something I once noticed I did. I put my phone in the opposite corner of my room, and turned the alarm on to 3 A.M. I woke up the next day at 8, and checked my alarm. It had been manually turned off.

Try putting your alarm far away from your bed, perhaps in a cage or something else it takes precision to open. Put obstacles in your way as well, intended to trip you. Remember to put it at a high volume, too.

Edit: Normally I become lucid out of nowhere. Something happens that triggers lucidity (ex the other night someone gave birth outside of a bagel shop.) then I RC to stabilize.