I run with a hat because I like to be able to isolate myself and a hat helps. But it turns out that it isolates too much. On my 5k out and back, I avoided a low hanging tree branch on the out, but on the back I was so focused on keeping going and avoiding the stinging nettles that I didn’t see the branch because the visor of my hat hid it from me. Wham! Knocked my hat off. Luckily its was a small branch but enough to give me a bit of a bump.
So my grand piece of advice, now that I am a wiser runner, is don’t wear a hat. Or, you know, look up a bit more frequently!