Shortly before filming the prequel trilogy, George Lucas and Co. authorized a flood of new Star Wars novels. He called it the Expanded Universe (now Legends under Disney). Some were good reads, and a few (e.g., Shadows of the Empire) were great reads. But they fit together poorly. And as Lucas added novel after novel, they really didn’t work together.
By 2010 or so, the Star Wars ‘canon’ looked like unintelligible garbage. A few dozen or so authors wrote a long series of mostly self-contained stories about Luke Skywalker and friends. The stories didn’t necessarily contradict each other, but they veered wildly in terms of plot and characterization. They always added up to less than the sum of their parts.
In contrast, the Dune universe built a much more plausible franchise model. Two authors develop the plot and write each book. The Dune canon is a bit bloated, and some of the books aren’t good (and none are as good as the Frank Herbert originals), but it all fits together reasonably well.
