What is an 'ordinary' word? The first sentence threw me for this precise term, which was internally inconsistent with later in the article talking about second

What is an 'ordinary' word? The first sentence threw me for this precise term, which was internally inconsistent with later in the article talking about second or third+ English language users, or even, not mentioned in the article, first language speakers with differing backgrounds. A very odd term to use. I'd open simply with "Think of your audience, think of your goal" and on thinking of audience expand to "Think of your audience, of which there may be some you've not thought of, or it might just be yourself, and think of your goal, if any."