We moved into our house 5 years ago. We have two bathrooms. One upstairs. One downstairs. I have yet to do #2 upstairs and now that all this time has passed I am somewhat stubborn about not using the upstairs toilet for this purpose (peeing, I have no problem with).
I have no idea why this started, but I find the longer I go without doing something the more superstitious I become about actually doing it.
For this reason I have never smoked a cigarette - despite having smoked other things and at times feeling the urge to try a cigarette. I figured by the time I reached 18 and hadn't smoked one it would be silly to "break the streak". Whatever the reason, this one worked out for me for not smoking.
For much the same reason I haven't had a steak & cheese or a Whopper in about 15 years. And I love them both.
I generally put my right shoe on first, and feel a little funny putting the left one first if I happen to pick it up by mistake.