You only remember the ones where the plot goes totally off the rails, dialogue makes no sense, and acting is just bizarre. Whoever is writing this trash is chronically incapable of producing anything even remotely good. It’s either forgettably mediocre or experimental chaos and pure madness.
It’s what your brain is thinking about during your rest state. If your dreams are frantic, frighting, memorable; you’re not resting. If your dreams are forgettable, not troubling, you’re probably resting well.
Well that’s good news.
When I do remember my dreams, they tend to be bizarre, not troubling. However, occasionally dreams do contain stuff I’m worried about. About 10 years ago, I had a very thin phablet, and I was worried about bending it accidentally. Those thoughts also started creeping into my dreams, which certainly didn’t help that sort of thinking.