He never even began to implement the postal coupon idea, it was a scam from the start. https://www.smithsonianmag.com/history/in-ponzi-we-trust-640...

> Of course, there was no network of agents. Nor, for that matter, did Ponzi expend any effort to corner the market on postal reply coupons. A final audit of his company's assets after the whole business was over turned up $61 worth of the coupons, according to Dunn.