Here is a video I found recently that has to do with perceptions of our own performance and discrepancies between actual performance and perceived performance:
I find it very interesting that they hypothesize that the very skills required to do well are the same skills to see the true quality of a performance. It's rather ironic, really.
Recently I've been thinking about how we evaluate people's performances. Or rather, I've been thinking about how I, specifically, approach commenting on performances and my family's tendencies while commenting, which is mostly negative. So now I've posed the question to myself, after years of having been exposed to this type of criticism (some constructive, some not): Why do I find it easier to say negative comments over positive ones? What I've concluded is that I've been trained, to a degree, to be able to see faults easier than virtues, but maybe that's the same with most people. But as it is, I've been trying to improve my ability at giving compliments, which is causing me to have to analyze why I have an easier time with one, but not the other.