What was it that made the great leaders great?

Analyse the great leaders of history and you'll learn about the positive traits that enabled them to find success, whether it be wit, oratory skills, strength, or any number of different abilities. Yet in all the world many people have these skills. So is it more about being in the right place at the right time? Or would the right person always find their way to the top irrelevant of what structures they're pitted up against?