As Thomas Sowell correct explains in his latest article:

In short, this is not about improving the health of the American people. It is about passing something– anything– to keep the Obama administration from ending up with egg on its face by being unable to pass a bill, after so much hype and hoopla. Politically, looking impotent is a formula for disaster at election time. Far better to pass even bad legislation that will not actually go into effect until after the 2012 presidential election, so that the public will not know whether it makes medical care better or worse until it is too late for the voters to hold the administration accountable.  …this is not about the public’s health. It is about Obama’s ego and his chance to impose his will and leave a legacy.