Mosquito nets, particularly insecticide-treated nets [ITNs], are the most recommended method of malaria control in endemic countries. However, many individuals do not use them as advised. The current paper expands on a previous review published in 2011 which highlighted a need for more qualitative research on the reasons for mosquito net non-use. We present a systematic review of qualitative research published in the past decade to assess the growth and quality of qualitative papers about net non-use and examine and update the current understanding. A comprehensive literature search was carried out in MEDLINE, CINAHL, and Global Health, in addition to a citation search of the initial review. Relevant papers were screened and discussed. The critical appraisal assessment tool was used to ensure quality. Thematic synthesis was used to extract, synthesise, and analyse study findings. Compared to the initial review, the results showed a ten-fold increase in qualitative research on the reasons for mosquito net non-use between 2011 and 2021. In addition, the quality of the research has improved, with more than 90% of the papers receiving high scores, using the critical appraisal assessment tool. The reported reasons for non-use were categorised into four themes Human factors, Net factors, Environmental/Lifestyle factors, and Administrative/Economic factors. More than two-thirds of the studies were carried out in Africa, with lead African researchers in African institutions. Despite the distribution of free mosquito nets in malaria-endemic countries, new challenges to their use continue to emerge. The most common reasons for net non-use across all regions of Malaria endemic countries were discomfort and perceived ineffectiveness of nets. Technical challenges and improper net use dominated East and South African regions, signifying the need for dedicated and region-specific measures and strategies to ensure the continued usage of mosquito nets, particularly ITNs.