Hardly shocking, but it turns out people are much better at predicting the behavior of others than themselves:
Psychologists have identified an important reason why our insight into our own psyches is so poor. Emily Balcetis and David Dunning found that when predicting our own behaviour, we fail to take the influence of the situation into account. By contrast, when predicting the behaviour of others, we correctly factor in the influence of the circumstances. This means that we’re instinctually good social psychologists but at the same time we’re poor self-psychologists.
It’s interesting to think about what puts us in social-psychologist mode and whether we can switch that on for ourselves. Obviously it’s not natural, but it’s got to be possible, right?