The contemporary proliferation of bullshit also has deeper sources, in various forms of skepticism which deny that we can have any reliable access to objective reality, and which therefore reject the possibility of knowing how things truly are. These “antirealist” doctrines undermine confidence in the value of disinterested efforts to determine what is true and what is false, and even in the intelligibility of the notion of objective inquiry. One response to this loss of confidence has been a retreat from the discipline required by dedication to the ideal of correctness to a quite different sort of discipline, which is imposed by the pursuit of an alternative ideal of sincerity. Rather than seeking primarily to arrive at accurate representations of a common world, the individual turns toward trying to provide honest representation of himself. p. 65
Harry Frankfurt, On Bullshit. Princeton NJ: Princeton UP. 2005.
The other aspect to add is that when one is sincere one is not accountable except in a personal sense. So, “he meant well.” If the question is that of being correct, then my perceived credibility is on the line. For most of us, this is high risk stuff. So instead we take an easier way out — being sincere seems to be an individual option, a way to get along. And here’s the irony, because it stops us from actually being accountable, relationship becomes more difficult’ our being sincere ends up then in a kind of loneliness.