On March 21, 1947, congress passed the 22nd Amendment, limiting the number of terms a U.S. citizen can serve as The President of the United States. Two terms was the limit, for fear, if a person was in office for too long they could gain too much power in that office. Also, the greatest president we have ever had, Goerge Washington, felt that a two-term limit as convention and a bulwark against a monarchy, the very power they left to create a new one in the United States.
If it was felt that the president could gain too much power, why should it not be felt for a Congressman in the Senate or a Representative in the House. It seems like they get too consumed by what the party wants, or a person or special interest that may be buying their vote for personal interest.