If something is moving along reasonably well, tinkering around with it can make things worse as much as they can make things better.
Progress pushed too far can turn into regress. This can be seen particularly well in social settings. If you try to manufacture the world how you would like to have it run, there may be negative consequences beyond a certain point.
This may be some of the reason why we see political parties in power for four to eight years before they are voted out for the opposing group for a similar amount of time.
You can move a patient and accommodating person quite some way along towards your desired endgame. However, just as you gain confidence that you’ll be able to shift them to the end, they may reach a resistance point. And all the progress you thought you made, might start to unwind.
You may find yourself back where you started. Or, perhaps the momentum will take you back past the starting point to places you wished you’d never disturbed.
So sometimes you may be better off with some good progress and leaving it there. In pursuing perfection, you may pay a much higher cost than you could have imagined.