Apparently, writers do a different job and directors do a different job in films, which most of the filmmakers and film lovers fail to understand. While writers imagine in a big way and write, directors make sure that the layman feels the right emotion after seeing those visuals. Even some writers don't understand the job of directors here.
In recent times, many writers have accused that the directors are not giving proper value to them, and then started taking direction into the hand. Some of them believed that a wide-shot, close-shot and a dolly-shot will do the needful to direct a movie. But the failure of writers like Sreedhar Seepana, Diamond Ratnababu, Veligond Srinivas and mighty Vakkantam Vamsi is an example that direction is a different trade altogether.
All the above directors have directed their first film as director 1-2 years ago, and still struggling to get their next. This is not because they can't come up with stories, but because heroes are lacking faith in them that they could really direct. The likes of Surender Reddy and Rajamouli don't write a story themselves, but they know how to visually narrate it. That's the key.
On the other hand, new age filmmakers like Shiva Nirvana (Majili), Gautham Tinnanuri (Jersey) and Prashant Varma (Kalki) write and direct themselves because they understood the two crafts better.