Once your cycle completes, you should see 0 ammonia and nitrite. Its possible, but unlikely, you could see 0 nitrate depending on your bioload, and how heavily planted you are.
A heavily stocked tank even in a heavily planted tank is unlikely to have 0 nitrate. A lightly stocked tank, in a moderately planted tank, more likely to have 0 nitrate.
I would check you are doing your nitrate test correctly. Gotta shake the heck out of bottle #2 (assuming API master test kit).
How have you cycled the tank? If fishless how much ammonia have you been dosing?