Going to disagree with you here. Based on my experience I would have failed if I had planned on it being slow in the beginning. You have to be prepared for extreme expansion as well as slow growth.
For me, I hit the ground running when I landed a major corporate client within the first 2 weeks of business. The entire first year was a mess, not because it was slow, but because it was almost too fast.
Basically we did what we had to, to make it work. Since then it has been a game of making everything efficient and things have got a LOT better.
But you never know what is going to happen, to be truly prepared, you need to cover all possibilities.