I think they meant don't start adapting an unfinished property. A certain transphobic author had issues because the studios really needed her to finish books 5, 6, and 7, so they could hit their schedule of 1 movie per year for 8 years.
Edit: based on replies from the original commenter it seems that your interpretation was correct.

He also walked around the car to check her bumper stickers before he shot her.