Many people have great ideas and sit on them. Not out of laziness usually, but out of fear of the unknown. What if it doesn't work? Does the marketplace even want this? How will we get the word out? Overwhelmed, you sit on the idea, convinced that a solution will come and then you will move on it.
Then a new competitor pops up, implements the idea that you had long ago but never did anything with and gets all the glory (and the clients).
The problem in this scenario is not the competitor, the problem is you.