Especially because I really admire him as a businessman, let alone as an author. You see, he did one of the smartest things a Science Fiction author can do. . . he convinced the world he wasn't a Science Fiction author.
You see, there are a lot of people out there who view Science Fiction with a negative connotation. They think it's all aliens and thousands of years in the future, and all centered entirely around advanced technology. Of course, this is utter crap.
A good science fiction story will often contain some of those elements, but almost every good story ever written is fundamentally about people. After all, people are interesting. But, for people who don't read much Sci-Fi, people who think SF is always a certain way, they're not interested. They find out a book is SF, and they're ready to move on to something more realistic.
But, back to my point, there are people who will choose not to read something based entirely on it's categorization of Science Fiction. So, Michael Crichton comes along, he writes Science Fiction books, but, he doesn't call them Science Fiction. And, he doesn't market them as Science Fiction.
So, instead of selling to the Science Fiction crowd, he sells his books to everyone who enjoys fiction, many of whom are unwittingly reading Science Fiction, and liking it.
Oh, yeah, he also manages to be among the list of the best selling authors of today.
The moral of this story, is that if you ever write a good Science Fiction book, and you want to sell lots of copies, call it a speculative fiction book, or even just fiction, and try to sell it that way. ;-)