Nobody is perfect. Everyone have their own weaknesses: pasts, habits, limitations. It's not to say that you don't need to do anything about that—that would be a lame excuse. Everyone have to make themselves better.
But sometimes you cant change some of your weaknesses. No matter how hard you try.
In relationship, this is the Stop/Go factor. If your partner's OK with you and all of your "remaining" weaknesses, then it's a Go. This is what being "compatible" is.
Otherwise, it's a Stop and Bye. And there's nothing wrong with that. If everyone always accept their partner's weaknesses, there would be no break-up in this world, and first boy/girlfriend will always be your only boy/girlfriend (and consecutively, your forever husband/wife).
So, knowing that shit happens, should you make yourself better? Of course. It's for your own good.