Your shoulders do a fair amount of work whenever you perform back and chest exercises, but performing exercises that single out your delts are also important for the following reasons:

Real-life benefits:

Strong shoulders make most arm movements easier, whether you’re throwing a baseball, passing food across the table, or lifting a suitcase that’s a little too heavy. Virtually every upper-body exercise involves your shoulder muscles to some extent, so strengthening your shoulders enables you to lift heavier weights for chest and back exercises.

Injury prevention:

If your shoulders are weak, they’re going to take a beating even if you perform chest and back exercises perfectly. Shoulder exercises also can prevent weekend warrior–type injuries, such as a torn rotator cuff from a softball tournament, or slapping a puck into the garbage can that serves as your hockey goal. If your shoulders are weak, you can even injure yourself doing day to day choirs.

Self-confidence factor:

Open up any bodybuilding magazine / social media account  and you see headlines such as, “Delts to Die For” or “Sexy, Strong Shoulders.” Bodybuilders take their shoulder training seriously because they know that these muscles play a big part in their appearance, which, after all, is what bodybuilding is all about.