If you consistently fail (or give up) at the very last interview, there's something rather wrong.
Your median/average should be better.
They don’t have every candidate scheduled for the entire time of all the rounds. If you don’t pass earlier rounds, they’re not going to waste time (yours and theirs) hauling you through more rounds of interviews.
If you make it to the end of all of those scheduled interviews, there’s probably a very good chance you’re getting an offer.
9 hours just seems excessive. Other companies have "funnel" hiring processes like this and still manage to do it in 3 hours instead of 9.
> You do know
No, I did not know when I posted that comment. steveklabnik's comment was posted concurrently with mine, and I did not feel the need to scour the whole thread in case there happened to be an answer to this specific question from an Oxide employee. But thank you for the data point.