Re: What do elected executives do? What does implementation mean?
Not sure what you're getting at, but when the executive and legislative branches are controlled by different parties, the President or Governor does NOT "do only what the legislative asks them to do." Although legislation is controlled by the House and Senate, they frequently negotiate details with the executive branch. They usually don't want to waste time on bills that the President refuses to sign or vetoes. Although sometimes legislators seek a veto to score political points or arrange an override.
Here's an explainer. I am just a bill.