Motivational interviewing is an evidence-based counseling approach. However, its learning processes and their influencing factors are understudied, failing to address the suboptimal use of motivational interviewing in clinical practice. A participatory action research was conducted in collaboration with 16 primary care clinicians, who encountered similar challenges through their previous counseling approaches. The study aimed to facilitate and describe the clinicians' professional transformation through interprofessional communities of practice on motivational interviewing (ICP-MI). Data were collected using the principal investigator's research journal and participant observation of four independent ICP-MIs (76 h) followed by focus groups (8 h). The co-participants performed inductive qualitative data analysis. Results report that learning motivational interviewing requires a paradigm shift from health experts to health guides. The learning processes were initiated by the creation of an openness to the MI spirit and rapidly evolved into iterative processes of MI spirit embodiment and MI skill building. The intrinsic influencing factors involved the clinician's personal traits and professional background; the extrinsic influencing factor was the shared culture disseminating the expert care model. Previously described in a fragmented manner, motivational interviewing learning processes, and its influencing factors were presented as integrated findings. Considerations in elaborating effective MI training/implementation programs are discussed for clinicians, trainers, and decision-makers. Future areas of investigation are also highlighted calling forth the research community to contribute to knowledge advancement on health education in primary care.