The Tragedy of the Commons (or the Tragedy of the Unregulated Commons) is a mental model developed by Garrett Hardin, rooted in economic theory. The "tragedy" refers to a set of individuals who, acting rationally, independently and in their own self-interest can create a situation where they destroy the collective's long-term viability by depleting a common resource. 

The original example referred to individuals sharing a 'common' parcel of land for herding or fishing. If an individual utilised the common area more than their fair share, they may receive an individual benefit (a few more fatter animals or a larger catch), but if all individuals made this decision, the common land would be overgrazed or overfished ultimately leading to it's destruction.

The theory is often seen as an example of emergent behaviour, or the outcomes of individual interactions in complex adaptive systems.

In essence then, there is a failure to think long-term in favour of quick and immediate gains.

So what are some examples in Marketing & Advertising?