punctual - quotes and descriptions to inspire creative writing
There are times being late is rude, other times it is polite, different cultures view punctuality so very differently, some take times as estimates and arrangements as possibilities. For some being late is very serious and taken as offensive. All in all, it is relative and perspective is key.
Punctuality is polite, I always see it that way. It is a form of respect to take the effort to appear on time. There are always things that can make us somewhat earlier of later, but to start off on the right foot I find that it is better to have good timekeeping.