What should referees watch for during warm-ups according to preventative officiating?

Referees should closely monitor players for jewelry or illegal equipment during warm-ups as part of preventative officiating. This is crucial because such items can pose safety risks, both to the player wearing them and to others on the court. For example, rings, bracelets, and earrings can cause injuries if they come into contact with other players or get caught on the net or floor. By identifying and addressing these issues before the match starts, referees help create a safer playing environment and ensure compliance with the rules. This proactive approach is advantageous, as it helps avoid potential disruptions or penalties during the actual competition, thereby enabling a smoother flow of the game.