Band Reverse Fly

Attach the band to a stationary object at chest height.

Stand with your feet shoulder-width apart and hold the band with both hands in front of you.

Keep your arms straight and lift them out to the sides until they are parallel to the ground.

Squeeze your shoulder blades together at the top of the movement.

Slowly lower your arms back to the starting position.

Repeat for the desired number of repetitions.

Recruiting larger muscle groups to "help" move the weight instead of isolating Delts — swinging momentum or shifting the torso takes tension off the muscle this exercise is meant to train.

Locking out too fast or letting the elbows drift outward under load — controlling the eccentric (lowering) phase is where most of the muscle-building stimulus happens.

Choosing a band with too little tension to feel challenging at the end range, since resistance bands are weakest at the start of the movement and strongest at the end.

Skipping a warm-up set at lighter load/intensity — even "beginner" exercises benefit from a rehearsal set to groove the movement pattern before working sets.