The Los Angeles Dodgers are usually one of the most active teams in Major League Baseball every offseason, but save for their blockbuster acquisition of closer Edwin Díaz, they've mostly been in a catatonic state since winning their second consecutive World Series.
Mind you, getting Díaz was a huge deal, as the three-time All-Star patches a huge hole at the back of the Dodgers' bullpen. His 1.63 ERA and 38% strikeout rate will look mighty fine in the ninth inning while closing out masterpieces from Blake Snell and Yoshinobu Yamamoto.
Still, when that's your only notable addition of the offseason (unless you count re-signing World Series hero Miguel Rojas), you hardly qualify as one of the "most-improved teams" in baseball.