That’s because most people don’t know how to make them. When your presenter is basically reading the slides to everyone and making a few comments, they’re doing it wrong.

1. No text slide should be on the screen for more than 4 seconds. (2-3 is better) And it must be fully readable in that time.
2. Charts, graphs, and images can be up for as long as needed, but the only text should label specific parts.
3. Don’t use fancy transitions or pretty backgrounds for anything.
4. Breaking the above rules is okay once or twice, if you have a very specific reason for that specific slide.