The scapula needs to rotate upward when you raise your arm overhead. If it doesn’t, it may lead to shoulder pathology, and shoulder pain. Here are my favorite stretches for the lats and levator scapula - 2 important muscles that will limit scapula rotation if they are tight.
The Levator Scapula muscle goes from the shoulder blade to the neck. It’s job is to elevate the shoulder. It often gets tight with bad posture.
The Lattisimus Dorsi is a large muscle on the lower trunk. It’s responsible for extending the arm.