High dropout rates and low pass rates are prevalent problems encountered by online learning platforms, which greatly hinder the development of online education. Drawing upon the theory of attention allocation, this study aimed to investigate the factors influencing the effectiveness of Massive Open Online Courses (MOOCs), as well as the potential moderating effects. To address the limitation of using course completion rates as an overall measurement, this study endeavours to measure MOOCs learning effectiveness by examining dropout rates and pass rates as separate outcome indicators. We use secondary data analysis to investigate our research questions. Specifically, we collect 8602 courses from a Chinese MOOC platform (Zhihuishu) using data‐crawling techniques, and employ regression analyses to examine our research hypotheses. The findings indicate that course quality, content richness and interactivity significantly influence course dropout rates and pass rates. Besides, content richness moderates the relationship between course quality and learning effectiveness. Furthermore, frequent online interaction is associated with lower pass rates in high‐quality courses, but the moderating effect of online interaction on dropout rates is insignificant. This study contributes to the extant literature by examining course‐level factors that affect learning effectiveness. It also offers new theoretical insights and provides valuable suggestions for the design of MOOCs. Practitioner notes What is already known about this topic Attention is a scarce resource, and the concentration level greatly influences one's academic performance. Excessive online interaction may cause distractions and hinder learning outcomes. Information overload can result in anxiety and negative emotions, thereby reducing one's willingness to continue learning. In addition, information overload may reduce perceived usefulness and negatively affect academic performance. High dropout rates and low pass rates are common problems encountered by MOOCs today, hindering the development of online education. What this paper adds This study investigates the effect of course quality, content richness and interactivity on course dropout rates and pass rates. Content richness moderates the relationship between course quality and course dropout rates / pass rates. Courses with more content have higher dropout rates and lower pass rates, particularly for high‐quality courses. Online interaction moderates the relationship between course quality and the pass rates. More frequent online interaction is associated with lower pass rates for high‐quality courses. Implications for practice and/or policy The improvement of course quality can contribute to lower dropout rates and higher pass rates, thereby fostering the healthy growth of online education. When evaluating high‐quality courses, not only the depth of course content but also the integration of resources should be considered. High‐quality online courses should carefully regulate the number of videos and manage online learning resources. In addition, it is recommended that course designers consolidate essential video resources and ensure the effective and appropriate structure of course content. High‐quality online courses should restrict the frequency of online interaction. Additionally, these courses should strategically help learners allocate their attention, with a particular emphasis on prioritizing the course video content. What is already known about this topic Attention is a scarce resource, and the concentration level greatly influences one's academic performance. Excessive online interaction may cause distractions and hinder learning outcomes. Information overload can result in anxiety and negative emotions, thereby reducing one's willingness to continue learning. In addition, information overload may reduce perceived usefulness and negatively affect academic performance. High dropout rates and low pass rates are common problems encountered by MOOCs today, hindering the development of online education. What this paper adds This study investigates the effect of course quality, content richness and interactivity on course dropout rates and pass rates. Content richness moderates the relationship between course quality and course dropout rates / pass rates. Courses with more content have higher dropout rates and lower pass rates, particularly for high‐quality courses. Online interaction moderates the relationship between course quality and the pass rates. More frequent online interaction is associated with lower pass rates for high‐quality courses. Implications for practice and/or policy The improvement of course quality can contribute to lower dropout rates and higher pass rates, thereby fostering the healthy growth of online education. When evaluating high‐quality courses, not only the depth of course content but also the integration of resources should be considered. High‐quality online courses should carefully regulate the number of videos and manage online learning resources. In addition, it is recommended that course designers consolidate essential video resources and ensure the effective and appropriate structure of course content. High‐quality online courses should restrict the frequency of online interaction. Additionally, these courses should strategically help learners allocate their attention, with a particular emphasis on prioritizing the course video content. [ABSTRACT FROM AUTHOR]