I'm rather of two minds about whether one should continuously be trying to improve... If you're strenuously trying to improve a lot of the time... it's easy to lose sight of what you're doing because you're so focused... The effort to improve gets abstracted and doesn't really produce results, I think...
For an example of self-improvement that has become completely lost and deluded... I honestly think of the XIII personality change experiments he brought up originally. Obsession levels of energy were being driven into that game of self-modification and improvement... But it seemed doubtful anything was changing - at a guess, I'd say the whole-process was merely making him more self-fascinated, with no real change at all...
Do we grow out, or do we grow in? Do we become different - or become more thoroughly ourselves as we clear out fears and misperceptions?
I don't really believe in an answer to these questions, but I get the feeling most of our paths move in a spiral. We'd like to think we're changing, but the path we cut only changes slightly each time... We'd prefer to move from A to B, but by the time we reach point B, we've traveled far enough to reach point Y...
So, should you try to be better than you are? I don't know that the trying really helps all that much... It seems like you move through the spirals a whole lot faster, but you cut the difference more narrowly... I remember a period where I tried and tried to act differently than I did with miniscule results... but in the end, I just grew completely sick of the effort... It felt like I was frantically moving nowhere.
Although, I'm fairly certain that gaining perspective allows greater changes... Sometimes it seems like the only thing that does help you grow.
But if someone does say, "Arright - that's it. I'm as good as I'll ever be. I've made it." I can't but help to say they're probably thoroughly misguided. Or self-centered or whatever. ..."The quintessence of what can be disappointing about an SJ individual."