Successful heads of businesses, government, or social movements are often hailed as great leaders. We assume that an organization that is successful, particularly one with a highly visible leader, achieves its success largely due to the leader's efforts. An organization's success, however, can be completely unrelated to the company's leader, or can occur in spite of a bad leader.
Timing Can Be Everything. I recall decades ago hearing a talk on leadership by the founder of a rapidly growing regional restaurant chain, who was being hailed as a great leader. The amazing thing was that most everything this supposed expert leader was saying was contradictory to best leadership practices. He was a "command-and-control" type of leader who, with his COO brother, made all of the company's decisions. They later became known for their poor human resources practices. The company's success at the time was due to being in the "right industry at the right time," and occurred in spite of what seemed to be poor leadership at the top.
Over-Attributing Success to the Leader. We have a tendency toward giving leaders more credit (and blame) for organizational outcomes than they probably deserve. Two of my colleagues did a very simple experiment. They presented students with scenarios of a successful or unsuccessful work group and asked them how much of the success (or failure) was due to the leader. They did this study in the U.S. and Turkey. The leader was given far more credit for the group's outcome by the U.S. students (the U.S. is a very individualistic culture -we value individual initiative and effort), and far less credit than the Turkish students (a more collectivistic, group-oriented culture) gave to the leader.