From Ray McGovern:

In 2007, Adm. William Fallon, commander of CENTCOM with four decades of active-duty experience behind him, quickly took the measure of Petraeus, who was one of his subordinates while implementing a “surge” of over 30,000 U.S. troops into Iraq.

Several sources reported that Fallon was sickened by Petraeus’s unctuous pandering to ingratiate himself. Fallon is said to have been so turned off by all the accolades in the flowery introduction given him by Petraeus that he called him to his face “an ass-kissing little chickenshit,” adding, “I hate people like that.” Sadly, Petraeus’s sycophancy is not uncommon among general officers. Uncommon was Fallon’s outspoken candor.

The past decade has shown that obsequiousness to those above him and callousness toward others are two of Petraeus’s most notable character traits. They go along with his lack of military acumen and his dishonesty as revealed in his lying to the FBI about handing over top-secret notebooks to his biographer/lover, an “indiscretion” that would have landed a less well-connected person in jail but instead got him only a mild slap on the wrist (via a misdemeanor guilty plea).