Our founding fathers didn’t put it in the Constitution because they all felt that people understood that you were elected, you came, you served, then you went back to your law practice or your farm and someone else served...
You are SO CORRECT our founders NEVER intended for people to serve in government for a life time!!!! They intended citizens that were business owners, farmers, regular folks to serve and go home to return to their lives they KNEW somehow these BASTARDS would become addicted to power and corruption!!! Thus Article 5 !!!!!