Because Obama didn’t want his transition to be like Bill Clinton’s, which by all indications was an unmitigated disaster.
In 1992, the only Democrats who had run the White House in the past quarter century had worked for Jimmy Carter — and Carter’s tenure didn’t exactly inspire confidence. Clinton had James Carville — the most brilliant Democratic strategist at the time, and he had a lot of young guns. But he did not have a John Podesta to walk him through what it took to ran the White House, and certainly not a Rahm Emanuel.
The Clinton team thought that the cabinet mattered more than the White House staff, and spent a lot of time arguing, deciding, negotiating over cabinet picks. But the real power and control in Washington is centered in the White House…that was true even in the Bush White House with its high-profile roster of cabinet appointments. (David Addington, anyone?)
The White House staff was not named until just before Christmas — a mistake. They didn’t get their bearings until well into the administration.
All encouraging signs and hopefully it bodes well for what will come after.