It's Not What You Say... It's who you are when you deliver it. In an ideal world, good ideas, good concepts, and good jokes would be recognized right off the bat. In this same ideal world, people might not speak in banal sports analogies like "right off the bat."
What I'm getting at is something we can all feel as we try to make our way in the world. The focus here is comedy, but it applies to sitting in on a business meeting, or just trying to get people to listen in the schoolyard. Humor is subjective, and what that brings with it, is that it doesn't matter if your joke concept is great if no one's going to listen to it, let alone laugh at it.
When you come out of nowhere, no matter how good your joke, the audience needs something to connect them to you, something that has them rooting to laugh at your performance, even if, in some other ways, they might hate you. It shouldn't be about what they think of you as a person, just whether or not you're getting them to laugh. After all, not every comic persona is built upon being a lovable person.
The thing is, that you don't have to have any truly grand plan with your comedy. Everyone's version of grand is different. Maybe you just want to be able to tour, and you just want folks to laugh, for your own validation, or to crack through the shitty ice of day-to-day life. What I just mentioned as a goal I have done, on a stage, perhaps a grand total of never. That's just where I'd like to be.
So instead of blogging and not attending open mics or shows for six months, instead of grumbling about how you're funnier than the asshole/bitch/motherfucker you just saw on stage (you might be, you might not be, either way you'll still almost inevitably say this to yourself), remember telling jokes is a privilege, not a right, take advantage, and give people a damn reason to want to listen to what you're saying.