One of the worst offenders is Brazil. When living there, it was common to hear "I'm on my way" (to an agreed meeting point at a specific time) but that could mean they actually are on their way or that they've just got up from the couch and will go take a shower, choose what to wear, maybe have a bite to eat and then think about transportation.

Knowing this, the trick was either to not take specific times seriously or to give a fake meeting time (earlier than the actual one) so the person gets there on time.