The text discusses the importance of considering costs beyond just customer acquisition when growing a business. It introduces the concept of Customer Acquisition Cost (CAC), which is the total cost of acquiring a new customer, including advertising costs, salaries, and other expenses. The article explains that treating all ads equally can lead to suboptimal results, as different ads have varying levels of effectiveness. By considering CAC, marketers can optimize their investments and make informed decisions about where to allocate resources. The text also highlights the importance of Customer Lifetime Value (LTV) in understanding the revenue generated by customers over time, which helps determine the allowable CAC. Additionally, payback periods are discussed as a critical factor in determining how quickly cash is generated from paying customers. The article concludes that using costs and LTV to optimize programs can help drive growth, but cautions against "growth at any cost" and encourages marketers to partner with their finance teams to make data-driven decisions.