Leadership and kindness are not polar opposites.  They are not binary.  You can have one with the other.  In fact, kindness is an integral part of good leadership.  It is not kind to withhold critical performance feedback from an employee that would help them to improve.  In fact, it is actually cruel.  And it is not kind to simply delegate a task to a team member without providing them with all the information needed for them to succeed; it is actually lazy and mean. Leadership requires us to be more concerned about our team members than ourselves, to care about their performance, their well-being and their goals of becoming the truest, purest forms of themselves possible.  It means we must care about how things are going at home and not just about work and how we can help them when we can.  Kindness is not a sign of a weakness within a leader, but in fact it is the opposite.  The absence of kindness within a leader is often a sign of their own leadership immaturity and even incompetence; for these leaders are often more concerned about themselves than their team.  It is clear we need more kindness in leadership... how can you become more kind in yours?

Become the kind of leader that peole would follow you voluntarily; even if you had no title of position.  Brian Tracy

The greatest leader is not necessarily the one who does the greatest things. He is the one that gets the people to do the greatest things.  Ronald Reagan

Be kind whenever possible.  it is always possible.  Dalai Lama