Fraser, who is well known in the international community for his efforts to end apartheid in the early 1980s, told audience members that his greatest inspiration in life was Nelson Mandela, who he first met on a trip to South Africa in 1985.
The panelists warned future leaders against ignoring the advice of others, and relying too heavily on their own judgment.
"The main mistake of leaders is to overestimate their skills," Aho said.
Mahuad agreed, saying, "Ominpotence is the biggest mistake a leader could make."
One member of the audience felt the informal nature of the panel allowed the audience to see the human side of the leaders.
"The best lesson I took was from the human side of leadership they showed," said Mohit Daswani, a student at Harvard Business School. "They showed me you have to rely on your own values and beliefs to be a leader."