It doesn’t stop. Liberal or Conservative, Democrat or Republican, they’re all self-serving. Or at least enough of them are that the decent ones are completely overshadowed.
Even though our system is not officially two-party, it is so dominated by the pissing contests between them that progress becomes the victim, at the expense of the taxpayers.
What’s good for our country is irrelevant to these people; it’s only about advancing the elephant or donkey. In their efforts to discredit each other they both end up standing for nothing.