That doesn't mean that he didn't get any income until he spent the whole 7k. It could be that he spent the 7k over 6 months period (assuming 1-2 article per week for $100 each). He could have started earning a few hundreds of dollars and re-invested in his business.

It took him 4 months to reach $100/month in income and 6 months to earn $1,000/month, so it was an outlay of thousands of dollars before seeing enough income to pay for itself.