Your message and other things you say

At a technical conference, the audience had just sat through about 100+ minutes of technical detail and demonstration. It was interesting stuff (to them) but was quite a bit on the dry side and was a parade of facts and features. The conference organizers had invited a keynote to liven things up at the end of the session.

The speaker trotted out on stage and opened with, “Wow. That was a LOT of information. I guess you understood most of that, but I didn’t. I have no idea what it is you folks do.” That sure isn’t Rule #1 compliant, now, is it?! He then proceeded to mispronounce the name of the company who had hired him twice in the first 10 minutes of the keynote.
While the egregious (I love that word) error is not knowing the audience, a smaller error is admitting it, and essentially separating the audience from the speaker. A speaker should strive to build bridges between the audience and himself, not alienate and separate himself from them.

Know your audience and connect with them.