The rapid development of the internet has shifted retailing from offline to online, making it crucial for small and medium enterprises (SMEs) to leverage online sales channels to reach a broader audience and stay competitive. Given their limited financial resources, SMEs must make smart investments to avoid long-term risks. This book examines whether reducing latency and adopting mobile payments in e-commerce positively impact customer loyalty and conversion rates. Using Google Analytics data from 10,000 online shops worldwide over a year, a negative binomial regression revealed that lower latency correlates with higher conversion rates, especially among mobile users, who are more sensitive to delays. The positive effect of mobile payment adoption on consumer spending was confirmed only in the U.S., suggesting cultural or market-specific differences. The study contributes to existing literature by providing a cross-cultural analysis, highlighting the importance of optimizing latency in e-commerce, particularly for mobile users, to enhance conversion rates and customer loyalty.