Across five experiments, Klein and O’Brien found that this moral tipping point is asymmetric — a moral improvement takes a lot more work for us to notice compared to a moral decline, even if the evidence is we observe is the same in each case. In other words, “it is apparently easier to become a sinner than a saint, despite exhibiting equivalent evidence for change.”The researchers conducted the study using scenarios with a hypothetical coworker, Barbara. They described Barbara as having a neutral personality, but noted that she could occasionally be nice and other times be mean. They described her behavior as it occurred over a period of weeks, and asked participants how many weeks of consistent behavior it would take before they concluded that Barbara had undertaken a "moral change."
When Barbara’s behavior turned mean, it only took a few weeks for participants to conclude that she had taken a turn for the worse. However, it took many more weeks of positive behavior to convince people that Barbara was changing for the better.The authors explain their results, in part, with the negativity bias, which I blogged about during April A-Z.