The use of English articles is the most challenging task for the EFL learners particularly when there is no articles in their native language (L1). The purpose of this study is to investigate the underlying reasons for the difficulties in using English articles by analyzing the learners' own experiences. The data was collected in the form of written feedback from seventy-five adult Pashto (L1) learners of English (L2) having three different educational backgrounds. The data were analyzed by using qualitative thematic analysis software 'MAXQDA Analytics Pro 2020'. The results brought forth useful insights for learning and teaching the use of English articles for the adult EFL learners. The underlying reasons were found to be the failure in the identification of the concepts of countability, definiteness/indefiniteness of nouns, variability in physical form and concept of nouns, variability across languages, learners/teachers' attitudes towards articles, lack of article-check in computer software and pedagogical instruction.