This is pretty funny stuff…
The Emperor’s most trusted lieutenant and advisor, Darth Vader, was seen as an imposing and frightening figure to those who did not know him. This was because Vader, a veteran of the Clone Wars, had been injured in battle, and required a full-body suit to sustain him. The suit was generally considered intimidating, and coupled with the vast political power wielded by Vader, it generally became common wisdom that Vader was not a man to be crossed. Some Imperial officers even joked that Vader was a man who could strangle you with his gaze.
However, to those who knew him, Darth Vader was a warm and friendly man. His cold exterior was due to his need to maintain a level of professionalism in his work, which necessitated a certain degree of detachment. As a result, he rarely fraternized with his crews, which led to professionalism being confused with intimidation.