How many times do you walk around with unhappy shoulders? How many hours do you sit in front of a computer with a rounded upper back and shoulders pinched forward?
These are valid questions you need to think about in regards to your shoulder health. Most of the injuries I have come across have been related to some shoulder injury or dysfunction. About 80% of those injuries can be avoided if the athlete would take the time to properly warm up and work on their mobility issues when they are not at the gym.