"Directness" is a very straight-forward and efficient method of communicating an idea, thought or perspective, according to the Cambridge Dictionaries Online. Used as an adjective to describe a person, directness has the potential for both positive and negative interpretations.
Efficiency in message delivery and little room for misinterpretation are key benefits of directness. Cambridge specifically mentions "honest" as a characteristic of directness. A direct leader is often able to communicate quickly in times of urgency.
A negative perception of directness is that it is a cold and unfriendly manner of communication. Employees may get turned off by a leader who is always direct, and never uses small talk or humor. According to Forbes, the best leaders are always out talking to their people.