Because that's what everyone else is doing.
I can't believe the number of comments I have seen today on DKOS about how the president failed to lead, the Ds are the same as the Rs, the president is a failure and a disappointment because he didn't reform capitalism or convince racists to stop hating him.
It all seems to be Obama's fault. Not the electorate that stayed home in 2010 (and again now), not the electorate that does not know how bad income equality is, or that the deficit is down, or that health care costs are down. Not the media that quite deliberately played along, moving seamlessly from deficit hysteria to deficit invisibility over the course of a year. Nope, all Obama's fault.
Honestly, if he just said "Fuck it," and spent the next two years golfing while the Republicans dismantled the country and sold it piece by piece to the Kochs, I couldn't blame him.