Writing what you know is a well-intended piece of advice for aspiring writers that is too often misconstrued or misapplied. First, what we know is the result of our experiences, both good and bad, and also interesting and, frankly, boring. A long time ago, I spent a year as an industrial market research analyst, and my job was to analyze past sales patterns and forecast future sales of compressed air filters, regulators, lubricators, and valves used primarily in heavy industry. In the more than forty years since I departed that job, I have yet to find a way to make it terribly interesting to readers, except as a motivation to escape such detailed and precise boredom.

Yes, sometimes we do have experiences that are exciting, but if all you do with them as a writer is rehash the past, no reader will be interested. I’ve used my years as a Navy pilot not to relive the Vietnam years but as the basis for writing about piloting spacecraft, but even that requires integrating new information with old. What my experience does provide is the “feeling” of being in that sort of situation. The same is true of my years as a senior political staffer in Washington, D.C., where the experience and knowledge I gained become the basis for writing about politics in different governmental settings, in both SF and fantasy.

There are times, however, when using experience is counterproductive in writing fiction, and that’s when popular but inaccurate images and tropes have been fed so thoroughly to people that conveying what your experience has demonstrated is accurate conflicts with the popular images that are anything but accurate. I discovered this with The Green Progression, a then near-future SF mystery thriller I wrote with Bruce Scott Levinson about environmental politics in Washington, D.C. Although it actually got a review from a D.C. paper praising its accuracy in depicting Washington politics, the book was a miserable failure in terms of sales, largely because, I suspect, its depiction of national politics was far more mundanely brutal and cruel than the glamorously exciting, body-filled, last-minute-escape-from-danger images created by both popular thrillers and movies. What’s ironic about that was, when, several years ago, I had lunch with the head of the consulting firm I once worked for, he laughed at the fact that we had essentially written a lightly fictionalized version of what his firm did… and no one believed it. He also paid for the lunch.

Experience does matter, because a wide range of experience makes it far easier to convey in depth different settings, occupations, and environments and how people react to such settings and occupations. How much it matters depends on what you write and how you write it… and the audience for whom you write. Page-turner thrillers, from what I’ve observed, rely on action and more action, and not as much depth in other areas is required. Novels that explore character through action generally can benefit from more experiential depth.

But like all sets of advice and all generalizations, there are authors and books that are quite successful… and go against every observation I’ve just made.