The 20th Amendment
On the surface, the 20th Amendment may not seem significant, but it did have important repercussions. It included six sections, but the last two were simply instructions as to how it would be implemented once ratified. The first four sections are where the substantive changes can be found.
In the first section, the dates on which new terms begin for members of Congress, the vice president, and the president were set. The terms for new members of Congress were designated to start on January 3 and the vice president's and president's term was set to begin on January 20. Prior to the 20th Amendment, there wasn't a specific date for newly elected officials to take office.
The dates that were being used would often result in long lame duck periods - the time between the day of election and the day someone left office. The loser of an election had less incentive to work effectively during these transitional periods, which is why they needed to be minimized. The 20th Amendment accomplished that. It also clarified provisions related to the vice president's succession if the newly elected president died between the election and the inauguration
