My mom used to tell us, "Shh, your father hasn't had his coffee yet." We all knew we were to tiptoe around until he did. Of course, I was usually the only one tip-toeing since my brothers weren't as geared to getting up at the crack of dawn. I didn't understand the apparent paradox of my father being an early-riser (so to me, a morning person), but not wanting to communicate with anyone.
Now I get it.
I've never been a late sleeper, but even before I developed the coffee habit, I was already developing the same pattern as my dad. I like to get up early, but I don't really need company. There's a quiet quality to early morning that I need. It's a time to center myself and mentally recharge. It's a chance to ease into the day. Before marriage and a family, that was easy to do. I spent the time in the barn with my horse. Feeding, picking out a stall, grooming and riding. I did them all before work. To me, those were peaceful activities that gave me a chance to recharge.
So if you run into me somewhere early in the day and I'm slow to say "Good morning," it's not because I'm having a bad day -- I'm just still in the morning zone. Stomp your foot and munch some hay -- I might even smile then.