The old custom may have begun as a practical answer to a problem nobody has now.

Customs often start as engineering and end as manners. Something was done because of a season, a shortage, a house layout, or a danger, and when the circumstance disappeared the habit stayed on without its reason. That is not a case for scrapping it, since a practice can be worth keeping for what it does now rather than what it was for then. It is a case for knowing the difference.

Take one rule you follow without thinking, at home or at work, and ask what problem it was originally solving. If the problem is gone, decide on purpose whether you still want the habit.