For all I know, he might be a great general, but he still needs to answer to this. From Bob Woodward's Plan of Attack:
Four days later, December 1, a Saturday, Rumsfeld sent through the chairman of the Joint Chiefs of Staff a Top Secret planning order to Franks asking him to come up with the commander's estimate to build the base of a new Iraq war plan.... "He had a month and we took 27 days away," recalled Marine General Pete Pace, the vice chairman of the Joint Chiefs of Staff and a Rumsfeld favorite. Franks was to report in person three days later. (Page 38)
What was happening in late November early December 2001? I mean, besides Tora Bora:
The Bush administration has concluded that Osama bin Laden was present during the battle for Tora Bora late last year and that failure to commit U.S. ground troops to hunt him was its gravest error in the war against al Qaeda, according to civilian and military officials with first-hand knowledge.... Though there remains a remote chance that he died there, the intelligence community is persuaded that bin Laden slipped away in the first 10 days of December.