Seems like you are mistaken negativity and fact, I myself said it was possible to do so in 4 years (Even though I do not do this for a living I do make a profit each year)
Now answers were based on the specific questions
If you know the market (flooded with single and lower double genes animals) and you breed Ball Pythons then you should know that making a profit with those specific animals by the time something hatches out and after deducting all the cost will just not happen.
To make a profit you need to make a sizeable investment and chose animals wisely.