No, no it doesn't. Are you talking about the recent movies that split the first novel into two movies? The novel Dune ends after Paul defeats his enemies and becomes emperor.

The Dune series has six novels, the final one is Chapter House Dune, which does in fact end mid story.

I know this because I read them in the 90s and didn't realise that Frank Herbert was dead for quite some time after reading Chapter House.

I know that, I've read them too. In the SP, and in this thread we're discussing endings to novels. No one is complaining about a series that isn't finished due to the author's death.

Hence my comment, "which is probably worse".