Ten slides, one sentence per slide, an arrow in the bottom right. The format is tidy, it flicks through nicely, and it holds you longer than any block of text. That is exactly why it became so common, and why it is so often empty.
The carousel is the only LinkedIn format that measures your attention slide by slide. Every swipe is a signal. A text post is read or it is not; a carousel hands the platform a curve. That changes entirely what is profitable to put in it.
The standard shape
Open three carousels at random in your feed. There is a good chance they all follow the same plan.
That plan is not laziness: it is optimisation. Ten slides hold attention longer than five, and one idea per slide reads without effort. The format rewards the number of swipes, not the density of what is found in them.
The summary test
There is a very quick way to find out whether a carousel says anything: try to sum up its contents in one sentence, without looking at the cover.
On a good carousel you will manage, and the summary will be shorter than the carousel. On the others you will notice you can only reproduce the opening promise, because it is the only thing that was phrased with any precision.
"7 mistakes killing your profile. Slide 4: Don't neglect your photo."
Layout techniques such as the carousel apply to the whole post rather than to a passage: they are flagged without highlighting, with the remark that goes with them. A carousel is never good or bad in itself; what matters is what it carries.
What a good carousel does differently
The format is not the problem. Excellent carousels exist, and they are recognisable by three things.
They carry a progression rather than a list: slide 6 depends on slide 5, and you cannot swap them. They contain at least one thing you could not have guessed: a number, a screenshot, a counter-example. And they are shorter than average, because somebody cut what was not earning its place.
A five-slide carousel with something in it holds up better than a twelve-slide one that is diluted, even though the platform prefers the second. It is one of the few places where the reader's interest and the algorithm's part company outright, and you have to pick one.