According to Katz (1955), the higher someone was in the organisation, the less technical skills were required to fill the position and more conceptual skills were required. On the other hand, the lower the position in the organisation more technical skills and less conceptual skills were required. However, human skills are always required no matter the level or the position in the organisation.

You can find the Figure presenting the skills needed for an Effective Administrator by Katz at the page. ("Skills of an Effective Administrator", by R. L. Katz, 1955. Harvard Business Review, 33(1), 33-42)

Katz's work in the mid-1950s set the stage for conceptualizing leadership in terms of skills, but it was not until the mid 1990s that an empirically based skills approach received recognition in leadership research (Northouse, 2007. p.43).