Online education industry has been growing strongly in recent years. The market for educational platforms that provides access to online learning is growing every year. With the increasing growth of online course enrollment, the interest of researchers to study the effectiveness of online learning is increasing. This paper summarizes the results of a study of online courses on the Stepik educational platform. The courses selected for analysis were divided into three groups according to the parameter of learners’ “reachability” to the end of training. The process of course completion by 36226 online course participants was analyzed. The main purpose of the study was to identify the factors affecting the yield parameter. The data obtained in the study suggest that the design of online courses does not affect the learning effectiveness and the yield parameter. We attribute such results to the fact that “instructional presence” and “social presence” are almost completely absent in the online learning process, as interaction with the instructor and other learners is minimized. “Cognitive presence” formed through interaction with the educational material is insufficient to form the level of engagement necessary to complete the learning. The study also identified the main points of “falling out” of learners from the educational process and formulated the strategies that learners resort to. The obtained data indicate that the parameter of profitability and effectiveness of online learning is most influenced by the qualitative (psychological) criteria of learners. The conclusion of this article suggests the main directions for further research, which can contribute to obtaining more complete data on the factors affecting the effectiveness of online learning.