So, you are saying that them staying for their 6 year terms as specified by the Constitution rather to than not staying, which was NOT specified by the Constitution, proved that the Framers plan didn’t work?
What was not specified in the Constitution doesn’t mean it was not understood by those in office HOW they were supposed to fulfill their responsibilities. They were elected by and understood to be serving at the pleasure of their state legislatures. They voted in the manner in which the legislatures directed them to. Very early U.S. Senators understood this, but in time, that duty and obligation (however not explicitly specified - a Gentlemen’s Agreement as I call it) slacked off until it ceased altogether.