some of the less... capable, engineers that I work with, they tend to avoid being honest with themselves and others; they talk themselves around admitting they don't know something, they bullshit their way through explanations to protect their egos and perceived social standing
ironically, in the eyes of myself and others, it has the opposite effect; among engineers, respect and hierarchy works differently than in other parts of the world. admitting you don't know something and seeking to rectify that gap is much higher status than already knowing all.