That is so true!
Think about it. So you do something wonderful, but in just a short amount of time, your success is forgotten, unless you do more for that success, topping what you've already done.
The same is true for authors. If you don't keep putting something new out, your sales will drop like an anchor. That happened to me in the past year, because no matter what I did, I didn't have time to put out anything new. Kids bugged me. Dogs bugged me. My health required me to do more moving and exercise. I couldn't get anything done and my sales have been reduced to almost nothing, even though I have 37 titles out there.
So keep writing and keep paving your road with more successes. Otherwise, you'll be forgotten and your 'success road' will disappear.
Have a great week!