Why might management be reluctant to prepare a formal job description for a position like "creative manager of content"? What are the pitfalls of not doing so?

One way to see the significance of work design and job analysis is to learn from what happens at companies that fail to define jobs. An anonymous employee of a multimedia company told Entrepreneur magazine's Scott Gornall about an editor who was given a new job title, "creative manager of content." Unfortunately, the scope of that job was never specified or explained to others in the company.
The new creative manager appointed himself to teach the others how to be more creative.
He placed some magazines in a cubicle and called a meeting to announce that, henceforth, that space was the Idea Lab, where employees could go to reflect on ideas. He drew up a flow chart to explain the Idea Lab. He called monthly meetings for idea sharing.
His colleagues, unimpressed, felt that he was disturbing their work in order to justify his new responsibilities, whatever they were. Perhaps in principle, a creative manager of content would have met a real need for this publisher, but because the position and its fit with the organization's objectives were never clearly spelled out, the idea was wasted.