The Timberwolves have won twice and lost twice so far in pre-season but Adelman believes that they cannot continue to go "through the motions" ahead of the new campaign.
"They've got to figure out what they want to do as a team," Adelman told the Minneapolis Star-Tribune. "I just told them, 'What kind of season do you want?' That's really up to us to make what we want. They've got to figure out what they want to do as a team.
"Like I told them afterward, we've played two games here at home and we're acting like we're just going through the motions. We aren't the San Antonio Spurs and we aren't Miami. We act like we have plenty of time.
"I know it's the exhibition season, but we're trying to get better and we really can't get better if we don't go out with better effort than we've shown."
Minnesota begin their season against the Orlando Magic on October 30.