Why would you need to practice them regularly even after the injury goes away? More often than not, the injury came about because of faulty regular movement, that changed the biomechanics, and then tension-stiffness-length relationship between the muscles.

So to use the previous Upward Rotation example, if you regularly do pull ups, you use your pec majors and lats to pull your arms down , in order to lift yourself up to the pull ups bar. The arms pulled down by the lats and pec pull down on the shoulder blades into a movement called Downward Rotation, which is opposite to what you want when lifting arms to the level of your head or higher. If you do the pull ups often enough without counter balancing it with the ‘rehab’ exercises of Upward Rotation, then the lats and pecs become stiffer, and maybe even shorter, and they pull down on your scapulae even when you don’t exercise, throughout the day. This in turn lengthens, and makes less stiff, the muscles that do Upward Rotation, like upper and lower trapezius and serratus anterior. This is the negative change to tension-stiffness-length relationship between muscles mentioned above. This makes it more difficult to move the scapulae into Upward Rotation, which in turn can cause pain in the front of the shoulder. To avoid it, do the ‘rehab’ exercises regularly, as often as you do the pull up exercises, or enough to feel like the ‘rehab’ exercises are easy to do, and there’s no pain. If you do that you maintain the correct tension-stiffness-length relationship between muscles.

Bottom line. Whatever you do regularly enough in the gym, playing sports, at work (can be sitting at the desk) can create injury, figure out what it is, and balance it with correct exercises (which mostly can be done at home) .