Everyone is watching a different angle, and sharing your knowledge with the team can empower the squad. Your teammates don’t have the same intel as you do, they are watching other locations and are engaging enemies in other areas of the map. If you keep them up to date with the enemies you’ve spotted, areas that you’ve cleared, and the utility that you can see, it increases your teammates’ map awareness.
The more information that you have should determine how you play. Do you need to watch your flank, is an area clear to rotate, should you cautiously move in or should you run? These questions can be answered through the team making frequent callouts.