I had a long conversation last night with an athlete about a long standing ankle injury she had recently re-aggravated. We were talking about strategies to mitigate her injury, and she quoted her doctor who said "We've been through this a few times, I don't think another 12 weeks of PT are going to help you that much." With which I totally agreed. What the doc was implying was that this woman should get operated on, with which I disagree.
Some folks have issues, joints, muscles, tendons, levers that just don't hold up. They have to be constantly maintained (assuming one doesn't just want to sit on the couch and watch Simpsons re-runs) some folks have accumulated a very high number of small injuries that have broken down joints or tissues, others have had a single catastrophic event that has created a long standing issue.. a lucky few (like me) have a combination of all of the above.
If any or all of these describe you, then you will probably need to manage and maintain your injury for as long as you intend on being active and pain free. You don't ever get to stop PT/corrective exercise if you don't want to hurt. It's just a fact of being you, sorry, suck it up buttercup. The good news is, if you stay on top of your maintenance you can continue to be awesome.
Similarly if you have significant dysfunction from your lifestyle (sit at a desk all day perhaps.. wear high heeled shoes all the time? ect) Unless you make significant changes to that aforementioned lifestyle not only do you have to do corrective exercise to get you out of a dysfunctional movement pattern or posture, you're going to have to keep doing some small amount of corrective exercise to keep you from returning to that dysfunction. To simplify, if your posture is terrible because you sit at a desk all day, you won't be "cured." Especially if you continue to sit at a desk all day. You are going to have to continue to do soft tissue/mobility/stability work to counteract the effects of what you do and how you sit those 40-60 hours per week.
Too often people want to be 'fixed' to be 'cured' with these types of movement and postural issues it's not that simple. You are fixed by keeping up on your preventative maintenance and making sure your dysfunction becomes and stays functional, and never becomes injury. If you have been injured, then making sure you keep that in the past tense will probably always be a part of your training. The up side is you get to keep training, and for 10-15 minutes of prevention will save you the pain and cost of a surgery or worse.