Here’s why someone in the back of the room fell asleep during your big presentation

Big presentations can be daunting. Even after weeks of preparation, it’s common to find yourself fighting off nerves, stumbling through slides, and clawing for the right words.

Here are potential reasons why your words weren’t resonating with everyone while at the podium.

You sounded too much like a salesperson — they stopped paying attention

Talk to your audience, not at them.

Author, strategic advisor, and speaker Ian Altman writes in Inc. about “selling too much” during a presentation.

“You might be given the stage to address the audience at a conference. This can be a disaster. You might consider pitching the audience on your product/service. Don’t do it!” he writes.

“Instead, share stories of challenges you’ve helped others overcome. Make the customer the hero, not your company. You want the audience to think, ‘I have a similar challenge, and I would love to have the same outcome as that person in the story.’ … Stories engage. Selling from the stage is a direct path to the vortex of evil,” he continues.

You gave them too much time to twiddle their thumbs

Get prepared beforehand so you don’t have to waste time — in an working world with too many meetings, you’ll need to make every minute count.

Bernard Marr, an author, keynote speaker, business, technology and data expert, writes on LinkedIn that “technical difficulties” can be an issue during a presentation.

“There’s nothing worse than sitting around and waiting for a presenter to figure out how to make the projector work — or worse, listening to a presentation without slides because he couldn’t make it work,” he writes. “Be prepared to connect to anything; a few dollars spent up front to buy all the right connectors will save you tons of embarrassment and headache. Know beforehand the kind of projector, the size of the screen, and the layout of the room so you can be prepared for anything.”

Your slides were too dense

Load up on these, and your audience will be out like a light.

Debbie Fay, founder of public speaking coaching, presentation development company bespeak presentation solutions, llc, writes in Forbes about how “creating visuals that aren’t aids” is a problem.

“[Y]ou should never show slides, or overheads, or flip charts that are text intensive. Period,” she writes. “Your visual aids should always be something that says what you (with words) cannot. Get it? We’re talking charts, graphs, pictures, cartoons, music. Any visual aid you create should act as a synergistic component; it should illuminate in ways that are beyond you and your words.”

Think of it this way: the less text, the better.

Your words were going over their head

Author Nancy Duarte writes in the Harvard Business Review that “speaking in jargon” is a common presentation error. This post was the last one in a series featuring information from her book the HBR Guide to Persuasive Presentations.

“Have you ever listened to a presenter who sounded super-smart without having any idea what she really said? If so, the presentation was probably full of jargon. Each field has its own lexicon that’s familiar to experts but foreign to everyone else. Unless you’re speaking to a group of people who are steeped in the material themselves, you’re better off avoiding highly technical or industry-specific language. Use words that will resonate with those whose support and influence you must earn. If they can’t follow your ideas, they won’t adopt them. Consider whether your presentation passes the ‘grandmother test’: If your grandmother wouldn’t understand what on earth you’re talking about, rework your message,” she writes.

The person was actually exhausted

Getting four hours of sleep + a long presentation = zzzzzzz.

Let’s not forget about this one — no matter what, don’t give them a reason to rest up during your presentation.