Leaders hear a disproportionate number of lies. More often than not, it's because they have created the conditions by which being lied to is advantageous to the liar.
Sometimes leaders have oversized egos that feed on bogus flattery. Thus, the lies. Sometimes leaders use their power to punish those who speak inconvenient or painful truth. Thus, the lies. Sometimes leaders so desperately want to hear only good news, or never hear bad news, that "rewards" flow toward those who fashion their reporting accordingly. Thus, the lies. Sometimes leaders build false and impregnable images of themselves, which require persistent fortification. Thus, the lies.
The wisest leaders I know engage in two practices that mitigate the need for lies: Transparency and Vulnerability. They actively seek truth from all quarters, and they make it safe for truth speakers to report freely.
Oddly, the lies create an illusion of prosperity and sustainability while the (often painful) truth arms us with the needed information to correct wrongs and perpetuate right thinking/practices/behavior.
Like so many other elements of leadership, this paradox is best deciphered by those who are unafraid to LISTEN and LEARN.