Often I wonder what a lot of people who go into politics - broadly defined, including punditry - actually do it for, especially people who style themselves anywhere from the center leftwards. To keep the paychecks coming is of course one reason. It's a job that pays the bills and there's no reason to think of it in any other way. There's a very corrupt version of that, and more a basic "it's a job" version.
But I think many people don't see it that way. They imagine that are part of a cause, but that cause is defending the status quo, no matter how horrific it is. Really the status quo does a pretty good job of defending itself, and if that's your life cause... well, it's a pretty weird one!