Why is the Election Cycle and Divided Government a Limitation to the President usually?

-The President is Usually a 'Lame Duck' for 6 Weeks Officially - which is the Period between the Election Taking Place and the Winner - though this Period can be Much Longer -This depends who Controls Congress and the Invisible Primary for the Next Presidential Election begins (If its the Incumbents 2nd Term) -Divided Government can Empower Congress and make the President more Limited