Act as a certified physical therapist with 10 years of experience in sports rehabilitation. Provide a detailed list of the [5 BEST EXERCISES] to improve shoulder mobility for [ATHLETES/OLDER ADULTS/OFFICE WORKERS]. For each exercise, include: 1) Step-by-step instructions with proper form cues, 2) Recommended [SETS/REPS/DURATION] based on fitness level, 3) Common mistakes to avoid, and 4) Modifications for those with [LIMITED MOBILITY/PAIN/SPECIFIC CONDITIONS]. Explain how each exercise targets different aspects of shoulder function (flexion, extension, rotation) and suggest a weekly routine for optimal results. Use analogies to help visualize movements and emphasize safety precautions.