It is useful to set some form of alert/alarm for parts of your day.
Personally, I set alerts for scheduled appointments and phone calls, to ensure that I am not late or forgetting them. OK, sometimes I also have to set an alarm to remind myself to eat. But I am not setting an alert for every task I have set for my day.
Have you ever had an alarm go off and hit the snooze? Or had a computer alert pop up only to snooze/dismiss it – and promptly forget about what it was there for?
Too many alerts and alarms become noise and defeat their original purpose.
So, determine what are the really important items you need alerts for, and set them.