Provide one challenge posed by serving as a leader and one challenge posed by serving as a manager in each of these functions?

The Plucknette article suggests that there are considerable differences between being a leader and being a manager. Is it possible or desirable to be both? Chapter 2 of the Management textbook suggests that the four functions of management are planning, organizing, leading, and controlling. Provide one challenge posed by serving as a leader and one challenge posed by serving as a manager in each of these functions?