Cameras cause blindness. Carry a camera and you'll never see anything.
I try to follow regular routes when I walk, so if I find a wall that's been knocked down by a stolen car (or maybe a drunk, or maybe a drunk in a stolen car) I'll be able to return to later to make a photograph. I walked by the site of this accident for days carrying a camera, but it wasn't until I wandered past without a camera that the wall came down.
Walk around with a camera and garlic hanging from your neck and you'll never see a happy accident or a vampire.
I really don't know why I still carry a camera sometimes; it's like a hangover, or perhaps just a habit.