A few years back, Microsoft flew me out to their headquarters in Redmond. Twitter was just starting up and my book about the platform was flying off the shelves. They wanted me to talk to their executives about social media. I walked out on stage, as I had done so many times before, took the microphone, looked out over a room filled with some of the world's smartest engineers and most dedicated managers, and the first words that came into my head were: "Ladies and gentleman, please welcome the bride and groom to the dance floor for the first time!"

I didn't say it. I managed to bite my tongue but those post-college years as a wedding DJ have left an impression.

I also didn't start with a joke. I might have started with a humorous story. I might have thrown out a question or praised an audience filled with people who create the products that we all use every day. I might have used any one of a dozen great ways to dive into a talk, but I didn't start with a joke.

There are a few reasons for that.

Have You Heard The One About... Oh, You Have...

For one, it's hard! It's hard to tell a joke that will get everyone in the audience laughing. Even professional comedians miss sometimes, and they're trained and their audience are waiting to hear something funny. Even if you're good at telling jokes, and not everyone is, some people will always roll their eyes instead of doubling up with laughter.

Those people are lost. When you start a speech with a joke that fails, they'll be less inclined to listen when you move on to describe your company's plans, your product's benefits or your staff's achievements. Start with a joke and you're betting the success of your entire speech on an attention grab in the first sentence.

And even if it works, you can still do damage. Unless you're guest hosting on The Late Show, your audience will want to be informed, not entertained. They want to leave with knowledge and a sense that they've learned something. Of course, they want to enjoy the experience, and you'll need them to enjoy themselves if you're going to hold their attention. But the success of a business speech is down to how much your audience learns, not how loudly it laughs.

That doesn't mean you can't use humor. You should use humor. Great anecdotes can educate as well as amuse. Laughing at your own mistakes--hey, we all make them--will show that you're human and approachable, and get your audience chuckling too. Everyone who has ever run a business will have a story to tell about a funny customer, a product launch that went wrong or a promotion idea that was so ridiculous you thought would work. It didn't. When each one of those mistakes taught you something, you'll have a lesson for your audience, a chance to raise a smile... and a start to a speech that will hold your audience and keep them listening.