This is a shame because PowerPoint is a great tool, when used properly. It's a visual medium to communicate with human beings, who are visual creatures. So let's look at how to write better slide copy, starting with how PowerPoint goes horribly wrong:
Too much copy on a slide makes it look like hard work. You may read the first line and, if you're feeling generous, the second. You may even skip to the end, to find a conclusion. But that's it. So why have a slide like this in your presentation...? Dunno.
Solutions:
Redundancy is the needless repetition of words, phrases, sentences or ideas. It's a problem in PowerPoint because it turns a half-way decent presentation into:
But that's not what PowerPoint is for. (It's what Word is for. And the two are very different.) PowerPoint is intended to support the speaker. Not the other way round.
Solutions:
A common mistake in business PowerPoint presentations is taking a (long, boring, wordy) document, converting it into a bulleted list of (long, boring, wordy) points, adding some TextArt, transitions or animations, and calling that a presentation.
Solutions:
People are visual creatures, as I've said, and PowerPoint is a visual medium. Also, images are more memorable. So why use a long heavy paragraph, like this one:
...when you could just show a lovely full-slide image of a cat chasing a mouse?
Solutions:
Good luck. Yes, it takes a bit of time to create better copy for your presentations. And yes, you've barely got enough time in your life as it is. But better copy means better message delivery, which means better convincing, which means better results - and good results typically yield more money, more success and more happiness, right? So ultimately, if you write better slide copy, you'll be a happier individual.
* Alexei Kapterev, 'Death by PowerPoint'