People go around daydreaming about what book/movie/TV show they'd make if they got the chance, and writing it all in their head. Then some of them do get the ch

People go around daydreaming about what book/movie/TV show they'd make if they got the chance, and writing it all in their head. Then some of them do get the chance, and it turns out to be a big hit. People start thinking of them as a good writer/director, and ask them to make something else. But they had twenty years to write their first thing, and only one year for the second. So it flops. This makes it hard to turn valuable intellectual property into a hit. Previously succesful showrunners won't necessarily be able to pull off the same trick twice. There's a person out there with a perfect LotR spinoff in their head, but WB can't find them. There are people who can churn out multiple hits, but they all know how much they're worth.