Attention. Would you be interested in the amount of attention I'm paying to your problem? I might have had blink training. Or I might be procrastinating because I'm unsure. I often tell students to only ask one question per email message to which I can give a quick answer. If several deeper questions are posed the answer can take a lot longer. How public do I want to make the attention I spend on your issue? I'm sure it is a factor of reputation, attention and trust. It just needs the research :-)