Pessimists get a bad wrap, but a now one researcher says there's one type of pessimism, called 'defensive pessimism', that is actually beneficial.
University of Sheffield researchers, explaining that defensive pessimists set low expectations for the outcome of a particular plan or situation. They then envision the details of everything that could possibly go wrong to make these worst-case scenarios a reality.
It gives the individual the chance to plan out a course of action to try and avoid those potential pitfalls, and ultimately motivates them to do better.
When the outcome [is not as great] as optimists had hoped for, they take a bigger hit to their wellbeing and experience disappointment and negative mood than your garden-variety pessimists.
However, the other main form of pessimism, which involves blaming oneself for negative outcomes, has far less positive effects on people. (thank you, Daily Mail)