The NBA's 2-3-2 finals format was implemented starting with the 1985 championship series, this format was adapted from MLB's World Series, which has used the 2-3-2 format since 1924.
The main reason for using this format was to consider the fatigue of the players during the finals. After several series of games, they were already very tired, and the finals were usually a confrontation between teams from the Eastern and Western Conferences, with America being geographically very wide. Flying back and forth on airplanes was time-consuming and strenuous. If the 2-2-1-1-1 format was used, the last three games would require flying across the country after every other game, which would greatly affect the players' condition.
