Maybe every year is just too much. It’s not that exciting, it comes too fast, and you're not sure who really cares.
Being born on this rare date, (and guilty of celebrating on off-years in the past), I’ll say that when the fourth year comes around for me, everything actually feels like maybe a birthday is supposed to feel— exciting, hopeful, a little childish. Everyone cares a little more, and that’s contagious.
5 years would be too round and regular, a depressing milestone. 6 is asking too much. 1,2,3— the stakes are too low.
It’s like the Wold Cup or the ancient Olympics.
4 is perfect.