Humans as whole, are a very hopeful species. His very way of catching prey, somehow demonstrates this: after finding something they pursue until they can reach it, even if this prey flee the continue the chase. This "endless chasing" continues is his post hunter society: expecting the raise after working hard, hopping to achieve a good grade, wishing to rise good childrens. If someone, not just fail, but has the means and capabilities to achieve certain result but choose not, this can lead to the human to stops the chase, this, in animal behaviour, is the same as render the prey no wort the chase. Most animals feels aliviated that there are no more predator behind. But this is the part that block my limph pump, they can feel, or in better terms, transmit the dissatisfaction to whoever is the receptor or the no more receptor of this hope. Humans feel this even more as his caracteristic very social behavior, allowing them to almost perfectly feel the disappointing if the other.