Who decides if there are more leaders?

Up to a point, the idea whether more leaders are needed comes naturally and it doesn't matter whether it is a company or the civil society. It is logical that if the workload in a company increases, new poeple shall be appointed there, all of whom needing management and mentorship. What is more interesting, however, is the situation with leaders in civil societies. Here the realisation that new leaders are needed is a long and challenging process. It is so because the search for a new leader starts only when there is a signifficant change in the way of thinking and accepting the reality. I believe that in such situation it is more accurate to say that the leaders are made not born because his/hers development is defined by these particular events. So, generally speaking, it might be said that the need for a change is what requires more leaders.