Whenever people find out I am writer by profession, inevitably the conversation leads to an idea they have for publication. It is humorous to me how many people think that having an article or book idea is equivalent to actually doing the writing. Understandably, non-writers don't realize that the true work behind writing is getting the words on the paper in a way that is relevant and palatable. I am betting most people on the planet believe they have a great idea for a novel, but how many of them will ever take the time to sit down and write an outline or a chapter of that novel?
Moving from thought to action divides mankind between dreamers and doers. While doers are often also dreamers, the reverse isn't necessarily true. Outstanding writers may make writing look easy, but I don't know a writer who really views their job as "easy." I teach writing and I often talk to my students, many of whom have solid ideas, but may not have what it takes to develop to word pictures that allow readers to truly envision those ideas. I am always excited when I discover a young writer who can express on paper what's in his or her head.
Writing requires thinking and imagining, but that's only first step of the process that results in a completed work.