Why Doesn't Contact Birthdays Trigger Alert on Notification Screen?

I am married...I guess I just have a better memory.
Come on now, unless you have a birthday to remember for every single day of the year do you really need to complain about the Contacts list not having notifications for birthdays.
2-3 birthdays every single month can easily be checked on a calendar (and that would be a lot) If its somebody that's important in your life and you can't remember the day of their birthday then their probably not that important. You might also need to set a notification for when Christmas is.
I have my parents, wife, kid and good friends birthdays/anniversaries memorized
Anybody else I would use a calendar...which has notifications.