Assume the best of people and the worst of circumstances. It just makes my life a little bit happier giving my friends and family, and even strangers, the benefit of the doubt.
Attribution bias. We have a tendency to attribute our own behaviours to external circumstances (“I’m driving slowly because I have good reason”) whilst attributing others’ behaviours to personal traits (“That person is driving slowly because they are incompetent”). It’s nice to remember that situational factors may be affecting a good person’s behaviour.