The correct answer to this open question is the following.
Unfortunately, you did not include any references or context. However, we can help you answer in general terms.
A modern-day leader has to achieve success in any endeavor he got into. That is why he leads a group of people or an organization, to accomplish the established goals.
To do that, the leader has to lead by example, so he/she can convince its people to do what it asks for. Otherwise, people would have doubts and concerns if the leader is not capable to do what it is asking for. That is why the leader has to show common traits such as patience, courage, flexibility, creativity, dependability, teamwork, and perseverance.