The only thing of real importance that leaders do is to create and manage culture. If you do not manage culture, it manages you, and you may not even be aware of the extent to which this is happening.
Edgar ScheinCulture is the deeper level of basic assumptions and beliefs that are shared by members of an organization, that operate unconsciously and define in a basic 'taken for granted' fashion an organization's view of its self and its environment.
Edgar ScheinLeadership is the ability to step outside the culture to start evolutionary change processes that are more adaptive.
Edgar Schein