Bad way to make a group decision

ALONE

Think of a word that describes how someone might try to decide for everyone without any input—it’s the opposite of teamwork.

The clue plays on the idea that making a group decision "alone" is a bad approach—since a group implies multiple people, doing it solo defeats the purpose. The word "alone" literally means by oneself, which humorously contradicts the concept of a group. It’s a straightforward pun where the answer is both the opposite of what you’d want and the literal interpretation of the clue.