Russian President, Dmitry Medvedev, commits three body language faux pas in this single photograph, which as a speaker or leader, one should never display. Whenever hands are clenched, particularly in an elevated position, the emotion of frustration present. Mr. Medvedev's down-tilted head with downcast eyes, in this context, are also highly consistent with frustration. Number three on this list is the act of covering his mouth - which is indicative of possible deception.
Dmitry is of course only human, and like the rest of us, he is much less cognizant of what his hands, face and body are doing in real-time than he should be. Becoming aware of such gestures in yourself make you more aware of these same behaviors in others. We all think we're observant, but few of us really are.