What caused BPN and BPP to accumulate losses?
After the financial crisis of 2007–08, it was known in 2008–2009 that two Portuguese banks (Banco Português de Negócios (BPN) and Banco Privado Português (BPP)) had been accumulating losses for years due to bad investments, embezzlement and accounting fraud. The case of BPN was particularly serious because of its size, market share, and the political implications - Portugal's then current President, Cavaco Silva, and some of his political allies, maintained personal and business relationships with the bank and its CEO, who was eventually charged and arrested for fraud and other crimes. In the grounds of avoiding a potentially serious financial crisis in the Portuguese economy, the Portuguese government decided to give them a bailout, eventually at a future loss to taxpayers and to the Portuguese people in general.
While successful predation results in a gain of energy, hunting invariably involves energetic costs as well. When hunger is not an issue, in general most predators will not seek to attack prey since the costs outweigh the benefits. For instance, a large predatory fish like a shark that is well fed in an aquarium will typically ignore the smaller fish swimming around it (while the prey fish take advantage of the fact that the apex predator is apparently uninterested). Surplus killing represents a deviation from this type of behaviour. The treatment of consumption in terms of cost-benefit analysis is known as optimal foraging theory, and has been quite successful in the study of animal behavior. In general, costs and benefits are considered in energy gain per unit time, though other factors are also important, such as essential nutrients that have no caloric value but are necessary for survival and health.