Why did the Framers create a system of appointing judges that required cooperation between the President and the Senate?

By requiring cooperation between the Executive and Legislative branches in regard to the particular task of appointing federal judges, the Founders (or, Framers) of the U.S. intended to establish balance in government and to avoid rapid (and radical) political change. No single governmental branch is able to appoint judges in their vital roles (balance); the process requires discussion, even debate (slow change).