It /should/ be an opportunity to reflect on your weaknesses, I don't think I've ever met a manager who would do anything but laugh at all-tens in a self-review, but I have been able to keep annual review conversations short and comfortable by expressing self-knowledge and making it clear that we both wanted me to improve in the same ways, but also that there are simply some areas I'm not as strong in as others, and I should be deployed as such.
In my view, the process has lost that purpose since it became a zero-sum game for determining raises, bonuses, and even layoffs. At the same time it's also a game for my boss, who's competing with other bosses at his level for his raise and bonus budget. He knows that I've been a supervisor, and that I understand the game as well as he does.
My boss accepts my all-positive self review, and then reminds me that I have to add two negatives, because it's mandatory. I choose negatives that are completely bland.
What it means is that dealing with my weaknesses is not part of the annual review process. But I'm free to engage in as much introspection as I want, and my boss is welcome to chat with me about it at any time. On the other hand, I might choose to keep some of my weaknesses to myself. Working through my own shortcomings is something that might be a rational choice. And there's such a thing as too much information. ;-)
