It's hard to know whether you're a good or bad kisser. Who's really going to have the gall to tell you? Is this an area that we actually look for constructive criticism in? Or is it better just to assume you're doing alright? If people continue to kiss you voluntarily, that's probably a good sign.
But whether you're the best kisser in the worst, or just okay, we all go through some sh*tty smooches from time to time. At least they make for funny stories.