Here a person's response to a stimulus weakens when it becomes familiar.[1] For example, with drink driving advertising in New Zealand, a decade ago we saw cars smashing into each other as a scare tactic. The content of these adverts has become less and less shocking the more we have been exposed to them. We have now become so desensitised to them that a humour approach has to be taken and the latest example is the ‘Legend’ advert.[23]