I understand in the sense that it is hard to be completely satisfied, even when it appears to have no defects. I know when I'm working I always think I can extract just a bit more gloss before sealing with a coating (I've used Opti-Coat but now used GTechniq C1 and EXO). There comes a time when you just have to say that's pretty much as good as it's going to get. That, and the marginal increases don't justify the amount of work that I continue to put into it.
Here's the thing that you need to remember, too. The paint is still going to get marred and scratched. The coating just helps keep it down, but over time, defects are going to start to show up, so you'll need to polish out the defects and and re-apply the LSP. Depending on your technique, it may be a few months or a few years before you'll need to do it, so you'll get another shot at polishing as soon as you want. Remember, there is no law saying you have to keep the coating. I've gone through a few trying to find the one that meets my standards the best.