I rarely need one anymore. I have a set time I go to bed & get up. It's been working for me for many years now. Only time I use it is to wake up with my husband for him to go to work. I'm not up at 4:30 am! lol
I always set one for work since I have to be awake at 4am, and I doubt I would wake up naturally at that time. Even if I did I'd still set an alarm though just to be on the safe side.
Recently I've used an alarm clock just to fix up my sleep patterns (there was a period of time where it was very bad). But now I just naturally wake up and I find it a whole lot better. I feel way more refreshed.
Same here , I don't need an alarm to wake me up in the morning unless I am waking up at different time than the normal one. And also when I am at vacation and travelling outside , I do need an alarm , which is my phone itself.