The second! Granted, early in my career when I was ghostwriting cheap kindle books, my clients were pretty uninvolved as they worked on volume but they'd provide me an outline and make a few notes.

At the level I work at now, where people are always paying five figures for a book, it's really involved. With non-fiction, my clients are telling me their own personal stories in as much detail as possible with hours and hours of interviews. That is something I don't think the "ghostwriting is unethical" crowd seems to grasp. Are we saying that only writers deserve to get their stories told? Because I can tell you, there are some beautiful, impactful stories that would mean nothing if written by someone with no experience. A lot of the time, it's just me taking their words and making them book worthy.

And then on the fiction side, my client and I usually collaborate very closely, they make a ton of editorial notes and changes. I also do something called book doctoring which is just line and developmental edits mixed with some writing. Nobody seems to think line editing is unethical but so often, a book is completely changed when I book doctor it. For me, it's the same concept. People have stories but writing is a honed skill.