The third step in designing a payment system UX is to optimize fees for user value and business goals. You can employ various strategies, such as discounts, rewards, tiers, bundles, or subscriptions, to encourage users to use your payment system more often, more consistently, or for larger amounts. For instance, you can offer discounts or waivers for frequent or regular transactions above a certain threshold. You can also reward users who refer new users, provide feedback, or complete surveys with credits, points, or cashbacks. Furthermore, you can create tiers or levels for users based on their transaction volume, value, or frequency. Additionally, you can bundle fees with other services or products that increase user value. Finally, test and measure the effectiveness of your fee optimization strategies by using metrics like conversion rate, retention rate, churn rate, average transaction value and customer lifetime value to evaluate how your fees affect user behavior and satisfaction as well as your revenue and profitability.