Where are the missing floors?
It is fairly standard practice in Hong Kong for buildings to have no thirteenth or fourteenth floors. They are considered unlucky numbers. Not sure what happened to the first, second and fifth floor here. And back-to-front button numbering that is neither in the telephone format nor the phone format. There’s a couple of lessons to learn here; when designing human-technology interactions consider cultural norms and existing design stereotypes. (Sorry, its the Human Factors conditioning in me that notices such things).