There was an article in Precision Shooting in which the author demonstrated that running the windage and elevation adjustments from one extreme to the other multiple times actually improved their function.
Once, at a benchrest match, a shooter who is a skilled competitor was getting groups that were considerably larger than they should have been, and the conclusion was that it was a scope problem. I asked him if he had ever tried "exercising" his turrets, to which he replied that he had not, and asked what I meant. I explained that it meant repeatedly turning them to their limits in both directions, and then back to their original setting. He tried it, and it worked. He went on to win a yardage with the same scope. It was a 36X Weaver. I think that sometimes we create adjustment reliability problems by not running our adjustments through a larger range than is required for making the small adjustments needed to go from 100 to 200 yards, or to readjust after changing barrels.