50. To Some, Time is an Illusion
There’s nothing more unprofessional than showing up 30-40 minutes late to an appointment without a word, and even worse to make a habit of it. If there’s a specific reason to be late once in a while, it’s at least good etiquette to let the person at the appointment know.
But to be chronically late and not take accountability falls into the category of being inconsiderate. It’s just poor practice. It doesn’t reflect well on the person, and if it’s a business setting, it might cause that business to take a hit by getting a reputation for being unreliable.