How to market a medical product?

How long does product/market fit last once you have "reached" it?

• In other words, couldn't your startup/etc. "lose" product/market fit over time? It may fit based on metrics today, but a year later, your market has changed enough to the point where "fit" is no longer there. How would you measure and better understand product/market fit decay?

• Answer:

  There's no one answer to this. Yes, you can have product-market fit and lose it. Ben Horowitz discusses this and other product-market fit myths in his post http://www.bhorowitz.com/revenge_of_the_fat_guy: Myth #1: Product market fit is always a discrete, big bang event Myth #2: It’s patently obvious when you have product market fit Myth #3: Once you achieve product market fit, you can’t lose it Myth #4: Once you have product-market fit, you don’t have to sweat the competition See the post for his elaboration on each. I'd say that you measure product-market fit decay in the same way you measured achieiving it in the first place—through key metrics such as active users, retention, conversion, or churn.