In a Ponzi scheme, scammers use funds from new investors to pay off older investors, creating the illusion of profits. Delayed shipping times can be an indicator of a Ponzi scheme in gold IRA scams because scammers may use the excuse of delays to buy time and avoid fulfilling their obligations. If a reasonable amount of time has passed and the gold shipment has not arrived, investors should consider it a warning sign and may need to take action to protect their investment.