Why is the president considered a lame duck president?

A president is considered a "lame duck" when they are near the end of their term and are not seeking re-election, or after a successor has been elected. During this period, their political power and influence can diminish, as legislators may be less inclined to support their initiatives, believing that the outgoing president will soon leave office. This situation can limit the president's ability to enact new policies or make significant appointments, as their mandate is perceived as weakened.