Understanding the complexity of motivation in the educational context is critical to improving learning outcomes and promoting student engagement, through an in-depth look at two case studies. , the author wants to point out the multifaceted nature of motivation, exploring its different aspects, determinants and meanings in educational settings. Furthermore, using qualitative methods, this article seeks to explore the nuanced mechanisms underlying fluctuations in motivation over time, considering both individual and contextual factors to inform discussion and conclusion on English learning dynamics in two typical cases.